Your commercial or industrial flat roof is leaking. What should you be thinking about as you consider your repair options?
Existing Roof Material
You need to know the type of flat roof material currently being used on your building.
There are three main types of flat roofing materials: asphalt, metal, and single-ply membrane. Generally speaking, flat roof repairs should be done in a manner consistent with the existing roofing material type, repairing like for like, so to speak.
An asphalt roof should receive an asphalt patch and a metal roof, a metal patch. Imagine you have a concrete driveway with some damage. Would you want someone to come out and install an asphalt patch? Probably not, the materials are dissimilar.
You would not want someone to install a concrete patch on your concrete driveway. The same goes for your commercial flat roof. Torch down modified bitumen should not be installed over an EPDM membrane to make a repair. The roof types are not the same and are not meant to interact.
Extent of Damage
The second thing you need to consider before attempting a repair to your commercial or industrial flat roof is the extent of damage to the existing roof. This will determine the type of repair that is needed.
In general, there are two types of repairs: minor and major.
An example of a minor repair is a small puncture in the membrane. A minor repair is something that would take one technician less than one hour to patch effectively.
An example of a major repair is removing and replacing wet or damaged insulation. That may entail cutting open a large section of the roof, removing the wet insulation, replacing it, and re-sealing the roof membrane. A major repair could take two technicians four to eight-plus hours to complete.
Major repairs should be completed in accordance with the manufacturer’s guidelines for the roof type involved. Never use EPDM rubber to patch a modified bitumen roof or install mod-bit over a metal roof. A TPO roof should receive a TPO patch. You cannot effectively weld PVC to TPO. You get the idea.
Ideally, major repairs should seamlessly integrate with the existing roof. With minor repairs like plugging a small hole, there is more flexibility.
There are roofing products that are designed to patch all three types of roofs. These patching products can be a godsend to the roofer and customer as they are quick, effective, and won’t damage the existing substrate. If you have a minor repair, like a small puncture, these patching products can be used to seal it up.
Jared Van Vranken is Vice President and lead estimator at Flat Roof Solutions in Malvern, PA. Jared has directed the installation, repair, recovery, and replacement of commercial flat roofs for more than a decade at Flat Roof Solutions. He guides clients in selecting the best roofing material for their needs and budget.