Reader's Response

In the article “Use of cladding in buildings here have grown in recent times” Mokhtar (2017), reported that although there are benefits of cladding installed on a building, cladding is still a fire hazard.

It is reported that the usage of cladding has shown to provide many benefits for the building, such as heat insulation and the reduction in energy consumption (Fadeyi 2017). However, cladding has contributed in rapid spreading of fire as air is sucked into the ventilation gaps due to pressure, which could escalate a fire (Budig, 2017).

According to the Singapore Civil Defence Force (SCDF), the ‘Singapore Fire Code’ regulates that the materials to be used in construction must meet the class ‘0’ requirement, which is defined that a fire will not spread when a material is ignited. These materials are required to adhere to local certification, which includes timely testing to ensure that there is no deviation from the requirement.

Although there are strict regulations in Singapore regarding fire safety, such as the ‘Singapore Fire Code’, there are existing buildings in Singapore with cladding which fail to meet the guidelines. A change in the checking and testing conducted on the material is required to ensure that the correct material is used for cladding.

“How did cladding woes happen despite layers of checks?”, Ng (2017), reported that the main cause for the non-compliance was directly from the source material, where the main material used for cladding was mixed with another material, which was non-compliant.

In the pre-construction phase, the materials are tested for the fire rating in batch samples at a certified laboratory, which will provide a certificate of conformity stating the matching serial numbers stamped onto the material. The certificate will be collected by the supplier, which will subsequently be given to the project architect.

In the construction phase, after the project is sanctioned by the architect, the cladding is delivered to the site, which will be checked by engineers to ensure that the materials are correct, as well as SCDF inspectors, who will provide a temporary fire permit. A contractor is often hired to install the cladding, who will then provide a separate acknowledgement of conformity.

In the post-construction phase, a certified external inspector is required to counter check the certificate of conformity, along with SCDF, which will then grant a fire safety certificate.

However, reported in the article “36 buildings may have combustible cladding that doesn't meet safety standards”, (Loh, 2017), 36 buildings were subjected to scrutiny, out of which 14 building were found to have cladding which failed to comply with the class ‘0’ regulation. These 14 buildings evidently show that even with despite strict regulations and checks, it has been unable to prevent a mix up of non-compliant material.

Although there are multiple checks done throughout the construction process, the material was only tested as a sample in the initial phase of construction. As the focus of the checks done by the multiple parties were to ensure that the material number matches the certificate of conformity, if the initial material had passed the laboratory testing despite being non-compliant, the subsequent checks would not have detected any abnormalities with the material.

A change of the material test to bench-scale testing will help resolve the problem of contaminated material. ‘Reduced-scale methods’ can be adopted to better test the material, as research has shown ‘good correlation’ with the full-scale tests, which provides a better gauge of the material’s fire rating (Wade & Clampett, 2000), as compared to sample batch testing.  Additionally, the material should be tested by another credited laboratory, to ensure that there is consistency in the laboratory results. By changing the testing methods, it could have detected the mix up of the material at the supplier’s warehouse, which would prevent this incident from occurring. Thus, with improved laboratory testing, the opportunity for incorrect material used in construction will be greatly reduced.

References

Mokhtar, F. (2017, June 17). Use of cladding in buildings here have grown in recent times: Experts. Retrieved from http://www.todayonline.com/singapore/use-cladding-buildings-here-have-grown-recent-times-experts

Loh, C. J. (2017, August 25). 36 buildings may have combustible cladding that doesn’t meet safety standards; police investigating. Retrieved from http://www.channelnewsasia.com/news/singapore/36-buildings-may-have-combustible-cladding-that-doesn-t-meet-9153588

Ng, J. S. (2017, August 25). How did cladding woes happen despite layers of checks? Retrieved from http://www.straitstimes.com/singapore/distributor-placed-two-models-of-cladding-in-one-stock

Wade, C. A. & Clampett, J. C. (2000, April). Fire performance of external cladding (PDF). Branz. Retrieved from https://www.google.com.sg/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&uact=8&ved=0ahUKEwjvkun01u3WAhUBGpQKHWIrBZ0QFghNMAk&url=https%3A%2F%2Fwww.abcb.gov.au%2F-%2Fmedia%2FFiles%2FResources%2FResearch%2FFCRC-PR-00-03-Fire-Performance-Exterior-Claddings.pdf&usg=AOvVaw3Gado4h7LpFOPrEHnHXxP7