Material defects usually arise from errors in the production process. Incorrect application may also contribute to damage caused to roofing materials, insulation materials, etc. For these types of specific damage, the inspection conducted on site is substantiated by laboratory testing. This method not only establishes the cause of the damage; it can also be used to determine the best repair method.
Because of the increased thickness of insulation materials in order to meet the requirements from the Buildings Decree and the sometimes limited ventilation, constructions become sensitive to condensation. Minor defects, for example in a vapour barrier, or an incorrect layering of the roofing construction may cause condensation problems. An inspection regarding the application method of the roofing construction and an assessment of the indoor climate conditions, supplemented by building physics calculations, may provide sufficient insight into the cause of the problems and the possible repair solutions.
The storms in January and February 1990 made it perfectly clear that things had to change. The requirements currently set for the wind resistance of roofing constructions have been tightened considerably. But even now, wind damage still occurs regularly. To be able to assess the wind resistance of bonded systems, BDA has developed a special test method by attaching peeling sheets or hinged wind beams to the roofing material. The sheets are secured to the pulling unit. The wind resistance is established by determining the amount of energy required to pull the roofing material off the structural deck. By comparing the test results to the calculated wind loads in the various zones of the roof area, it can be determined whether the roof has sufficient wind resistance.
We regularly see reports in the media about roofs that collapse during a heavy rain shower. Often this is caused by blocked drains, a lack of emergency overflow drains or a weakly designed load-bearing structure. To establish the cause of the collapse, an inspection is conducted on site, supplemented by a water accumulation calculation, which simulates the effect of increasing amounts of water that accumulate on the roof. Having a water accumulation calculation performed is also interesting as a precautionary measure to prevent the roof from collapsing.
Leaks in roofs are a commonly occurring problem. By using roofs for multiple purposes, for example a roof garden or parking deck, it is becoming increasingly complex to locate the exact water penetration points. Thanks to the experience of our consultants and the use of special equipment, the areas where moisture is present in the construction can be marked out during these inspections. The cause of the leaks can often be determined based on a visual assessment.
BDA has the required knowledge, experience and equipment to investigate all of these specific types of damage and to draw up a recommendation regarding the best repair method.