Put Your House In Order

Dear Readers:

From my experience in working among people in post-hazard environments, I can conclude that a stable house is the most prized possession. I have witnessed the grateful expressions of relief among those whose houses survived the tragic events.  The contrasting near hopeless expressions of misery among those whose houses were destroyed were almost unbearable.

It was after my first deployment to Haiti after the 2010 earthquake, that I finally understood that the primary purpose of an elected Government is to protect, as much as possible, the residents from foreseeable harm. It is for this reason why it is absolutely essential for each Government in the hazard prone Caribbean region to regulate the residential construction building industry in their country.

The Government of Barbados took the first step in trying to protect the public from certain post-hazard misery by publishing the Barbados National Building Code in 1993 [The Fire and the Fire Chief]. That was a commendable achievement because at that time, Barbados was experiencing an economic recession and political turmoil. Fortuitously, the national building standard was in place for the unprecedented building boom that would commence one year later, in 1994

It is a national disgrace that strains the limits of irresponsibility that the Government of Barbados, against all expert advice [The Construction Horror Show], allowed an entirely unregulated 14-year building boom with respect to building standards. Of the thousands of houses built, almost all of them are vulnerable to collapse in a major earthquake [Weapons of Mass Destruction]. It is to Barbados’ tragic misfortune that it would not have cost any additional money to have constructed the life-saving shear walls that the Building Code specified [Advice for Homeowners].

By 2010, the legacy of substandard residential construction was firmly established in Barbados [Happy Birthday Building Code]. At the start of that year, an earthquake in Haiti had reportedly killed approximately 300,000 people [In Defense of the Haitian Structural Engineer]. Near the end of that year, tropical storm Tomas examined Barbados and damaged over 1,500 houses. Following the visit, our Prime Minister reportedly made the following accurate observation: “I have to confess that I was flabbergasted at the fragility of the housing accommodation in Barbados.” [$37M Tomas Bill, Nation, 13 Nov 2010] He then reportedly recommended that it was “absolutely necessary to impose building standards in Barbados”, before adding the bewildering idea that a building code was “actively under consideration”.  With such ministerial statements, a strong response was eagerly anticipated.

Approximately two years later, around the 20th anniversary of the initial publication of the National Building Code, the Government of Barbados took the strongest possible action unimaginable. Against expert advice, the Government abolished the only national standard designed to help builders construct a house that could survive earthquakes and hurricanes [Good Code Gone Bad].

This act of utter stupidity placed Barbados in the unenviable position of being perhaps the only country on the planet that did not provide some type of structural building guidance to its residents. Even in the poorest country in the world, the Democratic Republic of the Congo, a homeowner could have found more relevant building standards than in Barbados. It is a national shame to which our apathy only encourages our Government to act more irresponsibly, to depths formerly thought practically unreachable.

It simply does not make any sense! Why would a Government allow an unregulated building boom, despite repeated warnings of the fatal consequences? [Is This Explicit Enough?] Why would a Government, despite acknowledging the fragility of Barbadian houses, then withdraw the only national building standard that could protect Barbadian households, despite repeated warnings of the fatal consequences? Should Barbados experience the inevitable major earthquake tomorrow, then these two actions, in retrospect, would be justifiably deemed unforgivable.

When we stand inconsolably near the rubble of our child’s collapsed school, or when we learn that our loved ones died in the collapsed commercial building, that is not the time to ask how it could have happened. If you have read this far, then you already know how it happened. What you do not know is why, and Barbadians have a right to know, right now! why they are being led to an inevitable destruction.

The Government of Barbados is fully aware of the estimated losses. The United Nations assessed Barbados’ infrastructure in its Global Assessment Report (2013) and placed Barbados in its worst possible damage assessment category for earthquakes and hurricanes, with no upper limit on the amount of damage predicted. Recent seismic studies of Barbados (Salazar et al, 2013) have shown that Barbados is significantly more at risk to major earthquakes than predicted by the UN.

Based on the latest earthquake design parameters (Bozzoni et al, 2011), it can be reasonably assumed that all buildings with reinforced concrete floors in Barbados, that were built before 2011 and not updated to the current design standards, are expected to collapse during a major earthquake, killing most of the people inside. This includes schools, houses and commercial buildings. Unlike hurricanes, earthquakes normally strike without warning.

To reduce the risk of fatalities, Walbrent College has prepared a Home Strengthening Guide to economically strengthen sub-standard houses against earthquakes and hurricanes [Home Strengthening Guide].  It is freely available on the Internet.

Best regards,

Grenville

References

Francesca Bozzoni, Mirko Corigliano, Carlo G. Lai, Walter Salazar, Laura Scandella, Elisa Zuccolo, Joan Latchman, Lloyd Lynch, and Richard Robertson, 2011.  Probabilistic Seismic Hazard Assessment at the Eastern Caribbean Islands.  Bulletin of the Seismological Society of America, Vol. 101, No. 5, pp. 2499 – 2521, October 2011.

Walter Salazar, Lyndon Brown, and Garth Mannette.  Probabilistic Seismic Hazard Assessment for Bridgetown-Barbados, Employing Subduction Interface Characteristic Earthquakes.  Journal of Civil Engineering and Architecture.  Volume 7, No. 11 (Serial No. 72), pp. 1405-1422, November 2013.

A Probable Cause of Asthma

Dear Readers:

It has not been proven what causes asthma in our children, and researchers have not proven the reasons why there has been a dramatic increase in asthma cases worldwide.  So researchers who can find a correlation with other factors often offer their speculative opinions.

In Barbados, incidents of asthma have increased significantly since the 1970’s.  Health researchers have blamed the sub-Saharan African dust and allergens, environmental researchers have blamed pollution, and climate researchers have blamed the climate.

It is very easy and convenient to find a correlation with factors that only God can change.  It allows reputable researchers to go unchallenged and offers no hope to those who are directly affected – mainly the children and their parents.  Since parents are essentially powerless to change the sub-Saharan dust, allergens and the climate, they must resort to treating the symptoms with drugs.

Treating symptoms is not a permanent solution, but it can be an unnecessary lifetime expense.  Therefore, let us turn our attention to this issue in order to bring relief to the sufferers, and to prevent further incidents.

Before we continue, let me note that preparing this article revealed a glaring weakness of peer reviewed documents.  Generally, the reviewer only know as much, or perhaps a little more, of the narrow discipline of their peer, the author.  However, most causal investigations are not confined to only one discipline.  Therefore, single-discipline reviewed research will always be incomplete and substandard.  This should not reflect negatively on the competence of the researcher or the reviewer, but rather, on the effectiveness or the system in which they operate.  I can confidently state that the conclusions of most (if not all) single discipline reviewed causal studies on multi-disciplinary issues that I have read, are as useful as a shoe on a fish.

When trying to solve these types of problems, the most logical place to start is to understand the following.

• The trend in the number of cases over many years.
• The variability in cases during any one year
• The relevant dramatic environmental changes when the symptoms started
• The relevant environmental changes that increased as the number of cases increased

What environmental factors changed dramatically in the 1970’s across Barbados?  Well, not the climate, not the allergens, and not the sub-Saharan dust.  In Barbados, in was mainly an increase in the construction of concrete-block masonry houses and the purchase of automobiles.

Before, the floors of houses in Barbados were not in direct contact with the ground.  Ground floors in chattel houses and stone masonry houses were normally suspended above the ground as shown below.

Builders constructing concrete-block masonry houses started placing the concrete slab directly on soil as shown below.

A child sleeping in a room where the floor is in direct contact with the damp soil is not a safe environment.  In recognition of this, national building standards worldwide, including the Caribbean, specified that a Damp Proof Membrane or Vapour Barrier (eg. plastic sheets) be used to prevent moisture from rising through the floor and walls.

Tragically, builders and potential homeowners in Barbados were not made aware of Barbados’ national building standards.  Very few, if any (certainly none that I was aware of before Walbrent College was founded 5 years ago) had a copy of the Barbados National Building Code.  Therefore, either the Damp Proof Membrane was not installed, or it was not installed properly.  In the photo below, the black plastic Damp Proof Membrane is not lapped properly and it is not taped at the laps, allowing moisture to rise.

In the photo below, the Damp Proof Membrane or Vapour Barrier does not extend over the blocks.  Therefore, moisture can rise up the walls.

Therefore, all children in single storey concrete-block masonry houses, and all children sleeping in bedrooms that were located on the ground floor of a two-storey house, were in an unhealthy environment.  If they slept in an unventilated room with the room’s door(s) and window(s) closed, then the risk of harm increased significantly.

 Supporting A Plausible Solution

At this point, the significant increase in the number of houses with the floor in contact with the ground is plausible.  Now, let us see if the trends of asthma cases support our proposition.

Since there is increased rainfall in the rainy season of May to October, the ground floor and walls of houses would normally be damper than during the drier season.  The statistics show that there is an almost doubling of asthma cases in the wetter months of May to October.

Further, the number of asthma cases are always higher in the lower catchment area that drains into the Constitution river, where the water table and damp soil is closer to the surface, than in any other part of Barbados.

While this does not prove causation, it certainly makes ‘concrete slab on ground’ construction method a strong contender.  The proof can come by interviewing the sufferers to see whether they resided in such masonry houses.  It should be noted that poorly installed vapour barriers is reportedly a common problem worldwide.  Therefore, it can explain the general global increase in asthma cases.

Investigating the Increase in Automobiles

For completeness, we should investigate the increase in cars, and thus car exhaust emissions, as a possible cause.  If cars were the reason for the increase in asthma cases, then we would expect to see significantly lower cases in the windward eastern side of the island.  However, generally, there are a higher number of cases per 1,000 people in the better ventilated windward side of the island than on the western side, excluding the Constitution’ river’s drainage catchment area.

Help for All Parents

So what can parents do?  My suggestions follow, which would improve the quality of the interior house environment, even if another reason is later proved to cause asthma.

All new houses should have a properly installed Damp Proofing Membranes (continuous plastic sheet, lapped and taped) under the ground floor slab and walls, to prevent the damp from rising into the house.

All existing houses should have the external walls plastered and waterproofed.  If you are renting, then ask the tenant to do this.  The photo below shows a typical single-storey plastered masonry house.  Note the rising damp areas at the base of the wall.

What you cannot see is that the builder did not plaster all the way to the footings.  Please be advised that this is typical.  Therefore, the walls below the ground are normally damp, and the damp rises into the house – especially if the Damp Proofing Membrane does not extend over the blocks.  Note that the right side of this damp area is drier, only because the soil has been removed.

The photo below shows a bituminous waterproofing agent applied to the plastered wall.

I wish you well.

Best regards,

Grenville

Note: All photos are copyrighted by the author.

Time to Wake Up!

The Government has indicated that a significant amount of the planned $2.5B new debt is to be used to build new infrastructure.  Before spending any of this money on new infrastructure, let me suggest that the Government meaningfully regulate the construction industry.

Having trained over 500 construction personnel around the Caribbean, I can confirm that much of our infrastructure is indeed substandard.  I have spent the past 15 years providing explicit evidence supporting the accurateness of this claim, and while some countries have heeded and improved, Barbados has gone backwards.

The United Nations recently assessed Barbados’ infrastructure and concluded in its Global Assessment Report (2013) that Barbados is expected to suffer probable maximum losses of over 80% of its gross fixed capital formation (buildings, equipment and infrastructure) if we are impacted by a moderate earthquake, or hurricane.  This is the UN’s worst possible assessment category.  For comparison, the UN predicts that neighbouring St Lucia is only expected to suffer probable maximum losses of 10% to 20%.  When will we wake up and realise that we are doing something terribly wrong?

If the Government is determined to put money into new construction, then why not also strengthen what already exists?  The cost to strengthen a house is in the order of 3% of the construction cost of the house.  So we either spend around 3% now, or at least 80% later.  We either go through a major earthquake or hurricane with minimal adverse impact, or we experience the misery of a national catastrophe.  The UN has determined that we are currently on the latter path, but if we are serious, we can change in a few months.

Strengthening properties requires both disposable income and knowledge of how to strengthen.  To address the disposable income issue, the Government can consider giving people a choice of either paying the new municipal solid waste tax, or using that money to strengthen their properties.

To address the knowledge deficit, Walbrent College has developed a Home Strengthening Guide that provides information to economically strengthen a house against earthquakes and hurricanes.  The Guide can be printed and given to a few contractors to complete for pricing.  It is freely available on Walbrent.com (President’s Blog section).

It appears that the dire warnings about the dramatic decline in construction standards in Barbados over the past 15 years was not convincing.  Therefore, let me present the likely scenario in a more dramatic way.

80% of our schools are expected to collapse on 80% of our students and teachers.

80% of our public buildings are expected to collapse on 80% of our politicians and public servants.

80% of our hotels are expected to collapse on 80% of our visitors and hotel employees.

80% of our commercial buildings are expected to collapse on 80% of private sector employers and their employees.

80% of our churches are expected to collapse on 80% of congregants and pastors.

80% of our houses are expected to collapse on 80% of Barbadian families.

Are we awake yet?  Some may consider this to be alarmist.  They should be aware that earthquakes give no warning, and an estimated 316,000 Haitians died unnecessarily under substandard buildings.  This is a necessary alarm.  Wake up!!!

Grenville Phillips II is a chartered structural engineer and President of Walbrent College.

Reference

UN Global Assessment Report (2013), pg 110, Figure 7.4
Can be downloaded free from:
http://www.preventionweb.net/english/hyogo/gar/2013/en/home/index.html

Distorting the Construction Market Place

It is generally agreed that many Caribbean economies are in crisis.  Economists normally view activity in the construction industry as a reliable indicator of the state of the economy.  However, the market place in which the construction industry operates is distorted to the point where it may not be an indicator that economists can confidently base their assessments.  There are two principal reasons for this distortion and they will be described in two articles, this being the first.

The construction industry is special.  It is a diverse sector that allows persons to enter at any skilled or unskilled level and progress as far as they are willing to go.  Conscientious unskilled labourers can become skilled artisans and technicians.  Artisans can become foremen, site supervisors, and contactors.  Technicians can become surveyors, architects, and engineers.  I have seen this progression happen with others and it is wonderful.

I started at the unskilled labourer level, wielding a cutlass to cut sight lines through dense vegetation, and holding the measuring tape and surveyor’s staff for the land surveyor when required.  The work was exhausting, the sun was merciless, and the weeks were long, but I was enthusiastically grateful for the opportunity.  I then took the technician route and worked as a draughtsman, then progressed to become an engineer-in-training, consulting engineer, director/employer, and now president of Walbrent College.  The construction industry is very special indeed.

The construction industry operates in a competitive market place of consultants, contractors, and equipment and material suppliers.  Each player has the opportunity to improve the quality of their work with each new project.  Government has one critically important role in the competitive construction industry, and that is to regulate a fair market place.  This includes ensuring that contracts are fairly awarded – much like how a referee regulates a fair competitive game of football or basketball and awards the game to the winning team. 

When the market place is fairy regulated, small players can become better as they compete with bigger players in the local market.  Big players have the capacity to compete regionally and internationally, but they must qualify by wining contracts.

The market place becomes distorted when the Government no longer regulates a fair market place, but instead selects favoured consultants and contractors, and shields them from competition by awarding them contracts.  This is equivalent to a referee awarding a game to their favoured team without even allowing the ball on the field of play.

During economic recessions, smart governments tend to spend money on construction projects for two principal reasons.  First, construction projects have significant multiplier effects (many people benefit from each project).  Second, local players can remain competitive and qualify for regional projects as soon as the regional economy improves.  Therefore, the most efficient use of these funds is to clearly define the work to be done, and then invite companies to fairly tender or bid for the work.  Simply awarding consultancy and construction contracts without fair competition not only distorts the market, but significantly harms the national economy.  Let me explain.

Simply awarding a contract eliminates the incentive to provide a competitive cost, and the accountability to do quality work.  Preliminary audits of recently uncontested projects suggests significant functional over design resulting in unnecessary costs in the order of 40%, and/or significant safety under-design to the point where the buildings are expected to collapse in an earthquake.

We had previously estimated approximately 75% of building losses during a major earthquake in Eastern Caribbean countries, mostly due to substandard designs that resulted from decades of poor competition practises.  In its latest assessment report (GAR 2013), the United Nations has determined that Antigua and Barbuda, Barbados, Dominica, Grenada, and Trinidad and Tobago are expected to suffer over 80% GDP losses from a moderate earthquake.  Yet, despite the evidence of wasted money, substandard designs, and independently projected catastrophic losses, these market distorting practises continue.

The real damage to the national economies of some of these countries is expected to be realised in 2014, which represents 5 years of the practise of awarding practically all contracts in certain categories to the government’s favoured consultants and contractors.  This practise of consistently picking undeserved ‘winners’, automatically disqualifies the most competent companies from competing in the regional and international arena.

The questions that many Caribbean governments need to consider are:  Why are you artificially propping up your least capable companies, and purposefully disqualifying your most competent companies?  If you think your favoured consultants and contractors are competent, then why shield them from competing with others in the market place?  Do you honestly expect these artificial ‘winners’ to successfully compete regionally and internally when you have harmed their development by protecting them from being tested locally for so long?

 

Happy Birthday Building Code

This year is the 20^th anniversary of the publication of the Barbados National Building Code (BNBC) for use by designers, building contractors and government regulators.  It has largely been ignored by its intended users.  Yet, it contains critical information necessary to design and build a house that should be safe during natural hazards.  Barbados is very fortunate to have had the BNBC at a time when so many expensive houses were being built.  Tragically, almost every house built during this time has been substandard.  The reasons follow.

For hundreds of years, proper building methods were passed from masters to their apprentices.  The last building boom in Barbados started around 1996.  It was fueled by mortgage institutions offering 95% to 100% to build houses.  This created a high demand for artisans in the residential construction sector.

The master artisans were generally working in the commercial and public sectors where quality control inspections by structural engineers were required by law to protect the public from unsafe buildings.  However, in the residential construction sector, such quality control inspections were not required, resulting in inexperienced and unsupervised artisans receiving masters’ wages for substandard work.

The building boom also provided an opportunity for designers to prematurely leave the employment of their mentors and start their own design practises.  However, while the structural designs of their commercial and public building projects were required by law to be designed by engineers, there was no such requirement for their residential projects.

This breakdown in mentor-ship created the perfect storm for houses to be both designed and built in a manner that left them vulnerable to significant damage during earthquakes and hurricanes, and attracting higher than normal maintenance issues.  A visit to any new (post 1996) housing development in Barbados will likely find no houses built with the critical life-saving shear walls as specified in the BNBC.  A visit to any residential construction site will likely find persons bending steel reinforcement to the point of failure, and then installing this useless material in the house.

To design the safety shear walls, and to bend steel safely, costs the designer, building owner, and contractor no additional money.  So why don’t they do such minimally responsible actions?  Incomplete mentoring results in persons not knowing that they do not know what they ought to know.

To address this knowledge deficiency, Walbrent College trains construction supervisors to build safe and durable houses in the Caribbean.  Any person building in the Caribbean should check Walbrent.com to ensure that their contractor’s foreman is among the approximately 250 persons already trained to build properly.

A Building Solution for Homeowners

The process of building a house for most people in Barbados follows these steps.

1.  The homeowner contacts a draughts-person or architect who prepares drawings and an application for Town Planning approval.

2.  The homeowner presents these drawings to a building contractor who provides them with a price, which if accepted, builds what is on the drawings.

3.  The homeowner occupies the house and is frustrated with the numerous and avoidable maintenance issues.

Most homeowners believe that the drawings approved by the Town Planning office contain sufficient information to allow their builder to build a safe and durable house.  This is not so. The drawings approved by Town Planning contain no guidance to the contractor to build safely.  Worse, most builders do not know how to build safely, and most if not all homeowners are oblivious to the fact that most of them occupy houses that will be unsafe during a major earthquake or hurricane.

I have often wondered what many of the 300,000 who died in Haiti thought as their houses, which they truly believed were well constructed, collapsed around them.  I have visited Haiti several times since the earthquake and have spoken with hundreds of survivors.  I understand that the dead have a different experience, but I can postulate that in addition to the fearful dread of impending harm, there was also a stunning shock and bewilderment about how their house, that cost them so much money to build, could be collapsing so dramatically.

Let me reiterate.  The drawings approved by Town Planning provide no guidance whatsoever to the contractor on how to build a safe house.  The homeowner is essentially placing hundreds of thousands of building materials into the hands of persons who generally do not know how to assemble them safely, despite their best efforts.  I have spent over a decade actively lobbying successive Governments to facilitate the safer building of houses, but there has been little change in the quality of residential construction practices.   So what is the homeowners’ solution when no-one is looking out for them?

I have decided to dedicate the next 5 years of my life certifying the competence of persons who are most likely to be responsible for supervising the construction of houses in the Caribbean.  These would include experienced artisans and construction supervisors/foremen.  The certification will be provided through Walbrent College, a Caribbean training institution for builders that is registered with the Barbados Accreditation Council.

If you decide to allow your contractor to build the typical unsafe and high-maintenance house for you, then you and your household will have to live with the consequences of your decision.  However, if you follow these simple steps then you should be OK.

1.  Ask your contractor for the name of their certified supervisor or foreman.

2.  Visit the Trained Persons section of www.Walbrent.com and check whether the named person is among the approximately 200 persons already trained.

3.  If no certified foreman is directing the construction of your house, then insist that the contractor send the person who is responsible for directing the building of your house to the 10-day certification course, which is offered in the evenings (6:00 pm to 8:00 pm).  The course includes an inspection of your site during a critical building activity.

The benefits to you and future homeowners is that you can avoid the typical frustrating maintenance problems, including: leaking pipes, cracked and blown floor tiles, rising damp in walls, cracked walls, and the premature loss of the roof and walls during natural hazards.

Regards,

Grenville

Introducing Walbrent College

While explaining the unplanned expenditure of $37M to address the damage caused by tropical storm Tomas, Prime Minister Stuart made the following observation:

“I have to confess that I was flabbergasted at the fragility of the housing accommodation in Barbados.”

The Prime Minister then reportedly stated that a Building Code was “actively under consideration”.

I promised that I would no longer describe the general sub-standard nature of the residential construction industry in Barbados.  However, I have a new strategy while I patiently await the actively considered Building Code.

Properly Train Construction Supervisors

Construction supervisors (including foremen), are critical to safe buildings since they are responsible for directing good or poor quality construction practices.  Foremen directing the construction of houses  have little to guide them, since there is very little structural information on the house plans that they are normally provided.  Therefore, they must guess at the sizes of footings, beams, columns, slabs, and rafters.  They must also guess at the amount of steel reinforcement in concrete elements.

Typically, the preparation of, connections between, and bracing of structural elements is inadequate.  This results in two types of defects, those which can lead to the partial or complete collapse of a structural member, and those which can result in higher than normal maintenance requirements.  It should be noted that the cost to build an unsafe house that attracts high maintenance activities is similar to the cost of a safe and durable house.  The amount of materials does not change, but their preparation, connections, and bracing differs significantly.

A Course for Construction Supervisors

Five years ago, I developed a course for construction supervisors to address the vulnerability of houses in the Caribbean to natural hazards.   This course has been taught around the Caribbean region.  I have now accepted the post of senior lecturer at Walbrent College, where I plan to teach the course in Barbados.

The six week course for construction supervisors is open to anyone with at least 5 years of construction site experience.  Graduates who successfully complete the other core courses of ‘Estimating Labour and Materials Resources’, and ‘Managing Building Contracts’, will receive the Diploma of Walbrent College.

Courses are scheduled to be held after normal construction working hours, on Tuesday and Thursday evenings, between 6:00 pm and 9:00 pm.  The next course is scheduled to start on Tuesday, 1^st February 2011.  Please contact Walbrent College at e-mail: Admin@Walbrent.com for registration information.  You can also get further details at www.Walbrent.com

The College is very accommodating to all prospective students, and a wide range of tuition payment options are available.

Who should attend?

• If you already direct construction activities and you wish to fill in any critical gaps of knowledge, then please come.
• If you want to learn how to properly direct construction activities, and you have at least 5 years of site experience, then please come.
• If you are building a house, and you want your foreman trained before he proceeds too far, then please send him/her.
• If you have a construction company and you want to have your supervisors well trained, then please send them.
• If you plan to build your house, and you do not want to be bamboozled by an unscrupulous contractor, then you may attend and receive a Certificate of Participation, rather than the Certificate of Competence.

The course will be taught using adult learning principles.  At the end of the course, supervising the safe and economical construction of durable structures should become second nature to the participants.  The ultimate beneficiaries of the College are the occupants of structures built under the supervision of its graduates.

Regards,

Grenville Phillips II BSc, BEng, MASc, MURP, CEng, FIStructE, FCIHT, MAPM, MCSCE, MBAPE

Fellow, Institution of Structural Engineers

The Fire and the Fire Chief

Since the fire of 3 September 2010, the Chief Fire Officer has been the target of much criticism.  My only criticism was of his excuse that Barbados only has a draft building code.  I found this excuse exacerbating because it appeared to be used to justify inaction on the part of the Barbados Fire Service that could have averted the tragic loss of life.

Does Barbados Have a Building Code?

Since the criminal act of 3 September 2010, building designers, government regulators, and politicians have identified the absence of a national building code as the principal reason for the deaths.  The Nation Newspaper editorial of 7th September 2010 also identified the principal reason for the deaths as “the sad lack of a national building code.”

For the record, the Barbados National Building Code (BNBC) was published in Draft form in 1992, and given to potential users for comment.  The cover states “DRAFT August 1992” in the top right corner.

After comments had been received, it was published as a final document in 1993.  For the past 17 years, the Barbados National Standards Institution (BNSI) has been selling the current edition of the Code for $100, for use by building designers, contractors, and Government regulators, including the Barbados Fire Service.

For the past 17 years, successive Government administrations have not made the enforcement of Barbados’ documented national building standards a priority. However, that does not absolve building designers, contractors, and regulators from their primary obligation to ensure that buildings under their authority are safe.  Barbados’ standards of structural and fire safety are defined in the current edition of the Barbados National Building Code.

Building standards are dynamic documents, and with use, are continuously being updated.  Sometimes errata are issued advising users of the updates.  When errata are inconvenient, due to the volume of changes required, then new editions of the standards are issued.  However, until a new edition is published, users should always use the current edition.  The BNSI is currently working on a new edition of the BNBC.

What Authority Does the Fire Chief Have?

The most voluminous section of the Code is Part 3 – the Fire Safety section.  It provides sufficient information to designers of new buildings in Barbados to significantly reduce the occupant’s risk of harm from fire.  It also provides sufficient information and authority to the Barbados Fire Service, to check the fire safety of existing buildings in Barbados, in order to significantly reduce the occupant’s risk of harm from fire.

The BNBC does not yet have the force of law that would give the Barbados Fire Service the authority to enforce the Fire Safety part of the Code.  Neither does the Fire Service act (CAP 163) give the Chief Fire Officer the authority to enter a private property to advise on, or enforce fire safety requirements.  Therefore, what can the Chief Fire Officer do?

Whenever I have asked the Barbados Fire Service to inspect large buildings and advise on their fire safety, they have responded.  They have always sent knowledgeable persons who have provided useful advice.  Such inspections have rarely exceeded 20 minutes.

If a fire officer could be assigned to visit commercial buildings in Barbados, and advise on their fire safety, I do not think that any business owner would refuse to grant access.  Therefore, the enactment of new laws to provide the threat of penalties for enforcing access is unnecessary.

Assuming that one fire officer can inspect eight properties each day in Bridgetown (at a rate of one per hour), then what is exacerbating to me, is that over 35,000 properties could have been inspected in the past 17 years – had the Chief Fire Officer been aware that our building standards were no longer in draft form, but was a final document that was being sold by the Government of Barbados for their use.

Blaming the Fire Chief

Do I blame the Chief Fire Officer for this lack of knowledge?  Of course not!  Why not?  Because if building designers, contractors, politicians, government regulators, and press reporters in Barbados have been insisting, for the past 17 years, that the Barbados National Building Code was only a draft document and not to be followed, and I alone am claiming that it is a final document, sold by the BNSI to be used, then history has shown that people tend to believe the majority opinion.  History has also shown that at critical junctures, where the consequences of being wrong were fatal, then the majority opinion tended to be on the opposite side of the truth.

Grenville Phillips II

Fellow of the Institution of Structural Engineers

In Defense of the Haitian Structural Engineer

Engineers worldwide share a common bond.  An engineer’s primary professional responsibility is to the public.  Therefore, Engineering can be likened to a “calling”, much like nursing.  Engineers take on significant responsibilities and their associated liabilities, and many feel that they are not fairly compensated for the work that they do – yet they continue to work.

Major national disasters, that test the built environment, can be viewed as opportunities to significantly improve national building practices.  These opportunities exist in every country, regardless of its level of development. 

When major earthquakes occur in any country in this world, we normally observe significant damage to older masonry and concrete buildings, whether they are schools, libraries, offices, churches, or houses.  We also observe less damage to recently constructed commercial buildings that would have benefited directly or indirectly from structural engineering services.  That is exactly what we seem to observe in Haiti, and it is exactly what we would expect to observe in London, Paris, New York, Madrid, Toronto, or Bridgetown.

The following are relatively  recently constructed multi-storey buildings that survived. 

             

             

Th following are older masonry and reinforced concrete buildings, and houses that were severely damaged.

             

             

During my deployment, I was surprised by the frequent attempts to associate the Haitian engineers with the damaged buildings, rather than with the recently constructed commercial buildings that survived.  I have not read of any attempts to link engineers with any of the damaged structures from the earthquakes in California, hurricanes in Florida, floods in Europe, the tsunami in Indonesia, and even the recent earthquake in Chile.  Why this apparent double standard?

 Why is there this effort to link Haitian engineers to the failed buildings which were unlikely to have received their structural engineering services.  Why this effort to show them as less-than-competent before international funding agencies and aid agencies, despite the fact that most buildings that appeared to have been designed by structural engineers did survive?

A reasonable explanation of this evidence is greed.  With approximately US$9B in development aid expected, a strategy of discrediting Haitian, and by extension, Caribbean based Engineers can ensure that they are never trusted with any primary design role in the reconstruction phase.  If this is a strategy that is  being employed, then it can partially explain why the group of qualified Caribbean based volunteer structural engineers have yet to be deployed.

UNOPS had expressed their concerns about the competence of the engineers being deployed by the various agencies in Haiti.  This was not surprising, since most, if not all, of those deployed by these agencies were unlikely to have the relevant experience of ever designing a building for the multiplicity of hazards experienced in the Caribbean.  The problem for Caribbean based engineers is the false perception that a North American, European, or Asian based engineer is intrinsically more qualified.

Let me conclude with some recommendations.  Engineers should not be deployed to disaster regions to displace the local engineers, but rather, to assist them where necessary.  Since the local engineers are the principal stewards of their country’s built environment, those deployed should try to improve the level of local design and construction practices.  There is a time and place for everything.  There will come a time for competitively tendering for work, but the critical relief phase is not that time.

Let me endorse Jesus’ recommendation that we should always treat others the way that we would want to be treated.  Let me also recommend the following approach by Lao Tzu.

Go to the people.

Live among them.

Learn from them.

Love them.

Start with what they know.

Build on what they have.

But of the best leaders,

When their task is accomplished,

When their work is done,

The people all remark

“We have done this ourselves”. 

 

Regards,

Grenville

Solving Barbados’ Flooding Problems

Why is there flooding in some areas of Barbados whenever there is a torrential downpour?

1.  The areas that flooded were not designed to accommodate the amount of storm-water.

2.  The areas were designed to accommodate the amount of storm-water, but the drainage infrastructure (drains and wells) were not properly maintained.

The maintenance issue can be solved by increasing the frequency of maintenance, and providing sufficient resources to do this.  The design issue can be solved with significantly less effort.

When designing a drainage solution, the designer needs to know the amount of storm-water that the drainage infrastructure should accommodate.  This amount of storm-water is normally expressed as the rainfall event that is expected once in, say, 20 years.  The designer can easily determine the amount of storm-water that is expected from a rainfall event that is expected once in every: 2, 5, 10, 20, 50, and 100 years.  Therefore, a lack of information is not the problem.

The principal problem is that there are no drainage standards in Barbados for designers to follow, and for Clients to insist be followed.  I believe that all drainage structures in Barbados should be designed for a rainfall event that is expected once in at least every 20 years.  If this drain is poorly maintained, then it should still work for a storm that is expected once in 10 years.  However, if the drain is designed for a 1 in 2-year event, and it is poorly maintained, then we should expect flooding whenever we get a torrential downpour.

Now that we know the principal problem, and we have determined a solution, it is up to the Government to simply state that from henceforth, all drainage facilities in Barbados must be designed for a minimum 1 in 20-year rainfall event.

Weapons of Mass Destruction

UPDATE:

One solution to reduce the vulnerability of your house is to have your foreman properly trained.  I now offer a training course that will lead to participants receiving the Diploma of Walbrent College.  See article on  Walbrent College for further details.

Regards, Grenville

END UPDATE

President Bush is looking for weapons of mass destruction.  He need not look too far.  Anyone who has visited a construction site in Barbados would have seen them – you just have to know what to look for.

Observe this fellow as he proudly demonstrates how he is ensuring that the multi-storey building will collapse like a ‘house of cards’ during the first major earthquake, probably killing everyone inside.

The minimum safe bending radius for British Standard steel is 3 times the diameter of the bar for bars up to 20 mm.  Therefore, for the 12 mm diameter bar above, the bending radius should have been a minimum of 36 mm.

The problem is that the fellow is only using part of the bar bending equipment – the part that holds the bar in place.  The round former is missing.

Question: What bending radius is typically used in Barbados?  The answer: 3 mm.  No, I did not omit an integer.  The round former is rarely used.  3 mm is completely unsafe and will almost certainly fracture the bar, rendering the anchorage component utterly useless during an earthquake.

The next question is: how much more will it cost for the builder to bend the bar around a safe radius?  The answer: $0.00.  That is correct.  It will cost him absolutely nothing.

Bu..bu..but what about the extra time?

OK.  How much extra time will be spent bending the bar around the safe radius?  The answer: not one additional second!  That is correct.  It will not cost any more money, nor will he spend any more time.  You did not ask, but, it will not take any greater effort either.  Actually, it will be easier for the fellow to bend the bar around the safe radius than the unsafe one.

Why then are builders ensuring that our children will perish in school buildings, and parents will perish in office and public buildings during a major earthquake?  That answer is simple.  They simply do not know that they are building death traps.

Aw, c’mon now.  It’s not that bad.  You’re just exaggerating and being sensational.

Oh.  I am sorry.  Let me reconsider my response, refine my answer, and tone down my delivery.

Two Chinese men try to calm a man, center, as he cries over the death of his daughter near a school damaged following Monday’s powerful earthquake in Hanwang town in Sichuan province, China, Wednesday, May 14, 2008. (AP Photo/Andy Wong)

Parents cry over the body of their daughter killed in the rubbles of a junior high school building destroyed by Monday’s magnitude 7.9 earthquake in Dujiangyan, southwest China’s Sichuan Province Wednesday, May 14, 2008. (AP Photo/Kyodo News)

A woman cries over the body of her daughter at the collapsed Xiang’e Middle School at the earthquake site in Dujiangyan of southwest China’s Sichuan province Tuesday , May 13, 2008.  (AP Photo/Color China Photo)

A Chinese man mourns as rescuer covers a dead student near a school damaged following Monday’s powerful 7.9 magnitude earthquake in Hanwang town in Sichuan province, China, Wednesday, May 14, 2008. (AP Photo/Andy Wong)

A woman mourns over the body of a student at the collapsed Juyuan Middle School at the earthquake site in Dujiangyan of southwest China’s Sichuan province Tuesday, May 13, 2008. (AP Photo/Color China Photo)

A Chinese man mourns the death of a student near the site of a school that collapsed in Juyuan, southwestern China’s Sichuan province, Tuesday, May 13, 2008. (AP Photo/Ng Han Guan)

A mother collapses after identifying the body of her child discovered from the debris of a primary school in Hongbai town in Shifang in southwest China’s Sichuan province Thursday May 15, 2008. (AP Photo)

These photos are disturbing, but they are real, and I wept as I inserted each of them.  China’s violently enforced one-child policy must increase the parents’ feelings of hopeless despair to immeasurable levels.  May they know the comfort that only God can provide.

The fractured reinforcement will be useless in a major earthquake, and all multistorey buildings that rely on them are expected to collapse during a major earthquake.

Why is our Government allowing builders to build death traps in Barbados?  Why is our Government allowing builders to build without having to comply with any building standards?

The only reason that I can come up with is that they are not looking in the right place when they jet off to China, where reportedly approximately 6,900 schools collapsed on thousands of students and their teachers during the recent earthquake.  I cannot be persuaded that our Government can see these images and allow the out-of-control building industry to continue in Barbados for one more day.

Over A Decade of Sorry Excuses

The building code is being revised.

That does not stop you from asking builders to comply with the existing Barbados National Building Code which was published in 1993.

We need to have national consultations on the revised Building Code.

That does not stop you from asking builders to comply with the existing Barbados National Building Code which was published in 1993.

The Building Authority is not set up yet.

That does not stop you from asking builders to comply with the existing Barbados National Building Code which was published in 1993.

The builders know what to do.

The inexperienced builders do not know that they do not know.  However, you know, but do not seem to care.  Why is that?

You Engineers are just being self serving and want more work for yourselves.

Generally, all of the technical advice normally offered by Architects, Planners, and Civil, structural, mechanical, and electrical Engineers are contained within the Barbados National Building Code.  Therefore, homeowners do not need to hire an Engineer for this advice.

We need to draft some more legislation.

No you do not!  Why are you so afraid of asking builders to build properly?  Good grief!

Regards,

Grenville

Related Article: Construction in China

The Worst House that the Code Will Allow

UPDATE:

One solution to reduce the vulnerability of your house is to have your foreman properly trained.  I now offer a training course that will lead to participants receiving the Diploma of Walbrent College.  See article on  Walbrent College for further details.

Regards, Grenville

END UPDATE

“If you built to the minimum standards of the Code, then you would only have achieved the worst building that the law will allow.” Tony Gibbs

The minimum building standards in the Barbados National Building Code (BNBC) are for persons who simply cannot afford to do any better.  To consciously build below these minimum standards is lunacy.  You not only guarantee a homeless condition for your family after a major earthquake or hurricane, but your house is likely to attract expensive maintenance requirements within 5 years of occupancy.

Homeowners and building contractors familiar with the BNBC may be tempted to adopt only the minimum standards, in the mistaken belief that complying with higher standards is prohibitively expensive.  I will therefore provide some guidance for home owners to achieve higher building standards at no or very little additional cost.  This should translate into a more structurally stable house that attracts lower maintenance costs.

The Design Stage

It is easier and far less expensive to make changes to a drawing than to a built structure.  Therefore, after you have received your drawings, critically review them.  Ask yourself:

• Is it what we really want?
• Are we happy with the layout of the bathrooms and kitchen?
• Are we happy with the location of lighting fixtures and windows?
• Are we maximizing natural lighting and ventilation?
• Are we happy with the ceiling heights, and size and layout of the closets?
• Does the house have the necessary shear walls at each elevation?

Now, more importantly, does your spouse understand the drawings?  If not, then use masking tape and layout the bathrooms, closets, kitchen and any other spaces as necessary.  Resist the temptation to be pressured into prematurely approving the drawings because you are getting frustrated with the progress.  Take your time to ensure that your spouse understands and approves the design locations and spaces.

The Construction Stage

Once you have approved the draughtsman’s or architect’s design, and the planning department has approved your development application, then your builder will set out or position your building on the lot so that he can excavate to find a stable foundation.

You should ensure that your house is accurately set out.  Your site plan should show dimensions from at least two corners of the building to the nearest boundary markers.  If it does not, then ask your designer to include them.  Once the builder has set out the building, check that the corner-to-boundary marker distances are in accordance with those on the site plan.

A stable foundation can be achieved by eliminating the risk of the building settling.  This means that you should excavate to a hard bearing layer.  If you have reached limestone, then allow the excavator operator to cut into the rock at least 75 mm (3″) in order to remove the weathered top section.  This can be done at no additional cost.

The Code specifies a 400 mm wide strip footing; however, builders normally use 600 mm, which is better.  The vertical wall reinforcement is 10 mm diameter reinforcing bars at 800 mm centres.  However, additional reinforcement needs to be placed at window and door openings and corners.  Take your time and check the spacing and location of the wall reinforcement.  Remember, it is your house.  The additional cost to perform this check = $0.00.  For clarification, there is insufficient reinforcement at the T-junction shown in the photograph above.

This is what happens when you do not measure carefully.

This is also what happens.  I travelled around Barbados searching in vain for an example of how it should be done.  The relevant autuorities need to arise from their slumber and acknowledge their responsibility to regulate industries that are out of control.  The residential construction industry is clearly out of control.

Concrete must be compacted, and a vibrator is normally used to remove the air voids to facilitate this compaction.  If concrete is not compacted properly, a condition called honeycombing results.  This condition can allow air, water and chlorides to reach the reinforcement and facilitate the corrosion process.  Compacting concrete should be done at no additional cost.

Concrete must also be cured to allow the chemical reactions that facilitate the hardening of the concrete and allow it to reach its design strength.  Concrete can be cured by keeping it wet continuously for 3 days, or by spraying the surface with a curing agent.  Ask your builder how he plans to cure the concrete.  If he does not know what you are talking about, then you are in trouble.  A house with a floor area of 280 square metres (3,000 sq ft) will require approximately 8 gallons of spray on curing agent, which costs under $300.

In beams and columns, bend the link ends into the beam and column in order to reduce the vulnerability to earthquakes and hurricanes.  Insist on this task which can be done at no additional cost.

Since I could find no examples of how this should be done, I bent the link end inward …

and fitted it around the column’s main reinforcement so that the fabricator will know what to do.

This is where I found it last weekend.  Why do I bother?  Because I care.

Use the correct type of reinforcement.  The British BS 4449 is stronger, less brittle, and can bend around smaller radiuses without fracturing.  Since the American ASTM A615 is cheaper and weaker, you will need to use more of it to get the equivalent strength.  Therefore the cost difference should be negligible.

Reduce the rafter spacing from 600 mm to 500 mm to increase the wind resistance of your roof.  Your builder may not charge you any additional money for this; however, if he does, then for a 10 m (30′) long house, you will need approximately 6 additional rafters at approximately $80 each (2×6 Purpleheart).

Please do not rely on toe nails like this to keep your rafters in place during a hurricane.  If you do not install BRC rater connectors or their equivalent, then prepare to be homeless.  The cost of the rafter connectors will probably be under $100.

You should use hardwood or timber treated for insects.  The additional cost of using termite treated Pine for a 10 m (30′) long house is approximately $220.  The cost of replacing all of your roof timber structure could be approximately 100 times that amount.

Increase the frequency of roof fixings to 150 mm (6″) spacing at the hip ridges, eaves, and any gable ends.  The additional material cost should be under $200.  In the photo above, more fixings (like at the eaves) is required at the ridge, gable end, and another row at the eaves.

If you intend to use metal sheeting as a roof covering as in the photo above, then use 0.5 mm (24 guage) thick sheets.  The 0.4 mm thick (26 guage) currently costs $2.01 per square foot of roof area, compared to the 0.5 mm at $2.46.  Assuming a 1,800 sq-ft roof area, the additional material cost is $810. (The labour cost should remain unchanged).  This is significantly less than your annual insurance premiums are likely to be.

This is what can happen if the roof sheeting is too thin and/or there are no spacer blocks under the profile ridge connections.  Photo taken by author after hurricane Ivan in Grenada.

Regards,

Grenville

Related Articles on this site:

500 More Sub-standard Houses

The Construction Horror Show

Advice for Homeowners

Can We Achieve Affordable Housing in Barbados

The Worst House that the Code Will Allow

Weapons of Mass Destruction

Can we achieve affordable housing in Barbados?

UPDATE:

One solution to reduce the vulnerability of your house is to have your foreman properly trained.  I now offer a training course that will lead to participants receiving the Diploma of Walbrent College.  See article on  Walbrent College for further details.

Regards, Grenville

END UPDATE

Barbados can easily achieve affordable housing; however, we are not achieving it for two principal reasons, each of which we are generally oblivious.

The first reason is that we are unaware that we cannot afford the substandard houses that we have built for the past 12 years.  The start of this current building boom saw inexperienced persons offering themselves as building contractors.  Fortuitously, national building standards were published 2 years prior; however, the inexperienced builders were not required to comply with them.

The second reason is that home owners do not plan adequately and therefore run out of money before the house is completed.  Home owners are normally unaware that they are building houses that they simply cannot afford.

I would recommend that potential home owners adhere to the following procedure to realize an affordable house.  The assumption here is that 100% of your construction budget will come from the mortgage institution.

1.  Go to your mortgage institution to determine the amount of mortgage loan that you qualify for.  It is critically important that you deduct an estimate of the bridging interest from this amount.

2.  Assume a construction cost of $250 per square foot of floor space. Then divide your actual loan by $250 and the result is the total floor space in square feet that you should tell your designer not to exceed.  Your house can be built for less than $250 per sq ft; however, you should have a buffer to deal with the risks associated with building like unforeseen ground conditions for your foundations.

3.  After carefully reviewing your design drawings, and obtaining Planning permission, select honest and competent builders by obtaining and checking references.

4.  Obtain a construction contract.  You can obtain a useful one from the Barbados Association of Quantity Surveyors for $15 (tel:246 228-0598).

5.  Obtain a copy of the Barbados National Building Code from the Barbados National Standards Institution for $100. (tel:246 426-3870)

6.  Include in the construction contract that the builder must not build below the minimum structural requirements of the Barbados National Building Code.  Complying with this standard can be done at no additional cost.

7.  Also identify in your contract a fair and technically competent adjudicator to whom both sides can refer disputes.

8.  Invite at least two builders to competitively bid on the project.  Before they provide their bids, ask them if they need any additional information.  You should ensure that the bidder is aware of the following: wall, floor, and ceiling finishes, roof covering, door and window types, lighting and plumbing fixtures, and the proposed construction contract.  If you have not decided on your fixtures, then ask them to quote for labour only on an assumed fixture.
9.  Regularly visit the construction site and see if you notice substandard work.  You can view some typical examples of substandard in the construction section of this website.  If your builder insists on doing substandard work, then dismiss him and find a more responsible builder.

10.  Do not pay your builder until he has completed each stage of work properly and in accordance with the national standard.

Regards,

Grenville

Published in the 25 February 2008 edition of the Barbados Business Authority.

Advice for Home Owners

UPDATE:

One solution to reduce the vulnerability of your house is to have your foreman properly trained.  I now offer a training course that will lead to participants receiving the Diploma of Walbrent College.  See article on  Walbrent College for further details.

Regards, Grenville

END UPDATE

I have come to the unfortunate realization that we are doomed to experience the misery and economic setback that other Caribbean islands experienced after being examined by major hurricanes.  These countries only paid attention to building standards after their buildings were weighed in the balance and found wanting.

I have given up hope that the Town Planning department will accept their responsibility to ensure that houses are both designed and built properly, until they actually see the devastation that they could have prevented.  I have also given up hope that the Ministry of Housing will accept its responsibility to ensure that their proposed 2,500 “units” will be anything but sub-standard.

During the past 12 years, I have rarely seen a house built that confirms to the minimum structural requirements of our national building standard.  It is very distressing to report that every one of those sub-standard houses could have been built properly at no additional cost.  There seems to be a strange belief among builders and homeowners that they can somehow realize good quality construction by simply wishing it to be so.

How did we get to this sorry state?  The start of this current building boom saw inexperienced persons offering themselves as building contractors.  This was a well known practise, and therefore it was critical that building standards be effectively enforced.  Fortuitously, the Barbados National Building Code had been published approximately 2 years prior; however, for some inexplicable reason, the inexperienced builders were not required to comply with these minimum building standards.  A timely opportunity was therefore squandered as the relevant authorities refused to accept advice continually offered during the past 12 years.

I have decided to no longer publish articles on the substandard building practises in Barbados.    If there is a single builder in Barbados building structurally safe houses, then please contact me and I would happily publish the construction photos and promote your business free of cost.

I will use this final article on substandard building to inform home owners of what to look for and what to do if they find it.  Most of the photos were taken within the past week.

This is a good start.  Found the building on solid rock.

Notice the layer of topsoil at the surface.  This will compress, therefore do not allow your builder to build upon it.  If he insists, then dismiss him.  The underlying layer is a mixture of predominantly clay and gravel sized soil.  The clay will compress, but it might also swell if it gets wet.  To avoid the risk of the building settling or rising, you should found the building on the rock.  If you do not believe me, then believe the Great Master Jesus who noted that wise men build their houses on rock if they wish them to survive natural hazards.  I believe that He indicated that you are just short of an idiot if you allow your builder to do otherwise and expect the same result.

The builder has excavated to rock, then placed fill on the rock and compacted only the top layer.  The builder will try to justify doing this by stating that it will give him a relatively flat surface upon which to build.  However it is in violation of the building code and introduces the unnecessary risk of uneven settlement.  If he does not found your house upon the rock in accordance with Jesus’ advice, then dismiss him and find a builder who believes.

You should have your builder drill down at least 3 m (10′) to ensure that you are not on a cap rock or over a void.  Remember, we do live on a predominantly limestone island.

The thickness of the footing should be at least 200 mm (8″) for a single storey house and 250 mm (10″) for a two-storey house.  Here we have 150 mm (6″), and below it is 100 mm (4″) which is clearly insufficient.  If he does not rebuild this properly at his own cost, then dismiss him.  You will save yourself a lot of unnecessary grief.

This concrete was not compacted properly, and a condition known as honeycombing is the typical result.  This honeycombing can provide a path for moisture and air to reach the reinforcement and facilitate its corrosion.  If he does not correct this at his own cost, then dismiss him and find a responsible builder.

Here, there is insufficient concrete cover protecting the reinforcement so that its corrosion is almost guaranteed.  If he does not repair this at his own cost, then dismiss him and find a responsible builder.

Regrettably, this will soon be covered up and the home owner will be unaware that the foundation is sub-standard.  Within a few years later, this home owner will be calling for an Engineer to find out why the house is cracking up.

If this is what your builder is doing, then ask him to redo it properly.  If he refuses, then dismiss him.  Why needlessly put your family at risk during an earthquake or hurricane because of his substandard work.

Partial knowledge is just as ineffective.  He filled the block’s cores correctly, but did not include the reinforcing bars.

This is what you want to see.

Here, the builder has only one side of each window opening reinforced.  I do not believe that he is intentionally doing work which he knows to be substandard, rather, I believe that he simply lacks the knowledge.  That is why the failure to require builders to follow national building standards is such an unnecessary tragedy.  BNBC 2.425.5 (b) specifies one 12 mm diameter bar either side of each opening.

This house is likely to be structurally unstable during a hurricane or earthquake.  Over 90% of houses built during this building boom are similarly structurally unstable.  They are not expected to survive the first major earthquake or hurricane.

I cannot blame the builders for this structurally unsafe practise, for they are simply building what is on the approved plans.  The fault lies with the inexperienced architects and draughtspersons who designed the houses, and with the Town Planning Department who should never have approved the sub-standard designs in the first place.  Unless your house has been designed by a structural Engineer, it should comply with the specified minimum structural requirements of the Barbados National Building Code (BNBC).

The BNBC (section 2.405.8) specifies that external walls must have shear walls to resist lateral forces from Earthquakes and Hurricanes.  These are to be one 3 m (10′) wide wall from foundation to roof level at each face of the house, and it must not contain any window or door openings.  If one 3 m wide shear wall is inconvenient to the design, then two 2.0 m (6′-7″) wide ones are permitted.  You are welcome to look in vain for such houses built during the current building boom.  What is more distressing is that to accomplish this would have cost all of $0.00.  You should therefore review your drawings and get the designer to make the necessary corrections with dispatch.

This is where a lot of damage is done.  There are basically two types of high tensile steel reinforcement that have been used during this building boom, the British Standard BS 4449 and the American Standard ASTM A615.  Since the American steel is 85% cheaper, builders prefer it.  However, one cannot simply substitute one type for the other.  The British steel is approximately 10% stronger; therefore if you want to use the American standard, you need to use more of it which makes the cost approximately equivalent.  In the photo above, the link ends should be bent into the beam.

The structurally unsafe aspect of the American steel is realized when it is bent around radiuses specified for the British steel.  The American standard steel needs larger radius bends and tends to fracture when bent around smaller radiuses.  This means that the beams and columns will likely be ineffective when they are needed most.

This is how roofs are typically built in Barbados and it complies with the BNBC.  However, it is vulnerable to high winds.

This is what happened in Grenada during hurricane Ivan in 2004.  I informed the relevant authorities that it was found to be ineffective near the start of this building boom.  However, to-date, they have not issued the necessary errata warning persons not to use it.  If your builder insists on using this roof connection, then insist on hurricane straps.  Ensure that they are made of stainless steel in order to avoid corrosion and their subsequent replacement.

Make sure that the frequency of roof connections are increased at the eaves, gable ends, apex, and hip ridges.  They should be at most 150 mm (6″) apart in the shaded areas and at most 300 mm (1′) apart in the clear areas.  Finally, do not pay your builder until he has built each stage of your house properly.

Best regards,

Grenville Phillips II

Related articles by Grenville Phillips II:

500 More Substandard Houses

The Construction Horror Show

Can We Achieve Affordable Housing in Barbados

The Worst House that the Code Will Allow

Weapons of Mass Destruction

The Construction Horror Show

UPDATE:

One solution to reduce the vulnerability of your house is to have your foreman properly trained.  I now offer a training course that will lead to participants receiving the Diploma of Walbrent College.  See article on  Walbrent College for further details.

Regards, Grenville

END UPDATE

The Government of Barbados has several roles.  One critical role is to regulate industries that are out of control.  The residential construction industry is out of control.

We have been fortunate as a country to have had a Government with the vision to establish national building standards.  The Barbados National Building Code was published 15 years ago, just before the current unprecedented building boom.  The Code includes much of the technical advice that the following professionals normally provide their clients:

• Civil Engineers
• Structural Engineers
• Mechanical Engineers
• Electrical Engineers
• Architects
• Planners.

Yet, for some inexplicable reason, the Government has not required that builders follow the national building standards.  In my opinion, requiring builders to follow the minimum building standards does not require the proclamation of any new laws.

Last weekend, I visited some residential building construction sites hoping that I would see some improvement in the residential construction building practices.  There was little good construction available for me to photograph, but the ubiquitous sub-standard construction completely filled my 1 Gigabyte memory card.

I cannot blame the building contractors, not the artisans they employ.  I believe that they are simply doing the best that they know how.  They need to be aware of and comply with the minimum national building standards.  Who is to make them comply?  I believe that is one of the Government’s roles.

Your medical doctor may be gravely concerned when she examines an X-ray of your chest, or she may recoil in horror when examining the blood laboratory test results, but you may examine the same and conclude that all is well.  Why?  Because you were not trained to interpret the evidence.  I will try to help you to interpret the following photographic evidence from various construction sites at different stages of construction.

Photographs – Copyright 2007 by Grenville Phillips II.  All Rights Reserved.

After setting out the building on site, the builder should excavate the area of the footings until he reaches a good bearing material.  He has found a sound coral formation at a shallow depth.  Very good.

The builder then builds form work to support the concrete strip footings.  Very good.

But what is this?  Oh please no!!!! (like all good horror shows, you get a peek at the monster before he is revealed in all of his gory).

The builder has placed a layer of marl fill on top of the good foundation bearing rock.  He has therefore introduced the unnecessary risk of the building settling and the resultant cracked walls.  He has also introduced unnecessary work which is translated into additional project time and cost.  Quoting the national standard: “Footings shall not bear on fill material.” BNBC 2.504.4

Oh good grief no!  The labourer has obviously taken great care in cutting this foundation trench by hand.  However, he has stopped before finding rock, which is a mere 150 mm (6″) below this.  He has introduced almost certain foundation settlement and the resulting cracks in the walls and floor, including any ceramic or stone floor tiles.  It would not have cost any more to ask the labourer to excavate an additional 150 mm to the rock.

What the ???  The corners of the wall are not tied together properly.  Let me show you how the building code specifies that it should be done.

Not tying the structural building elements together properly can result in the building shackling out and collapsing during hurricanes and earthquakes.

Oh dear!  The builder cannot properly compact the 600 mm (2 ft) thick layer of fill – it should be compacted in 100 mm (4″) layers.  In addition, placing that fill on the topsoil is almost guaranteeing the settlement of floors with the resulting cracked ceramic or stone tiles.  The national standard states that this type of floor “shall be prepared by (a) removing top soil and any organic material; … (d) filling with granular material, if necessary, in layers of 100 mm …” BNBC 2.507.2

Compacting the top layer of fill only compacts the top layer of fill – not the underlying layers.  Therefore expect settlement of the floor with the resulting cracks.

No vertical wall reinforcement, therefore the wall is vulnerable to collapse during an earthquake or hurricane.  The National standard states “Loadbearing block walls shall be reinforced vertically with minimum 10 mm mild steel bars at 800 mm centres throughout the wall.” BNBC 2.405.2 (c)

Structurally unstable wall – no shear panel.  Therefore vulnerable to collapse during an earthquake or hurricane.  BNBC 2.405.8

If the wall reinforcement is not accurately located …

… then the wall is not properly reinforced and becomes vulnerable to collapse during an earthquake or hurricane.

This is gruesome.  The national standard states: “No horizontal or diagonal chases for pipes or conduits shall be permitted unless specified by the designing engineer.” BNBC 2.405.3.

Pressure testing the water pipes for leaks – excellent!

Like I said, I have 1 GB of photos, but I do not have the time to transfer and comment on them all.  I shall therefore adjourn here and resume on another post later.

Regards,

Grenville Phillips II – Chartered Structural Engineer