Category Archives: Construction

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.

House with suspeded floor

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

Floor on fill

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.

DPM

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

DPM not over 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.

Plastered house

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.

Unplastered foundation wall

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

Waterproofed 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 20th 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, 1st 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