Commercial Flat Roof
A flat roof is one that has a slope of zero degrees (horizontal).
It can be made from metal, concrete, or other materials. In most cases the sloped part of the roof is only for drainage and does not provide protection from rainwater. On the other hand a pitched roof drains water off in all directions and provides more protection against leaks. A flat roof usually needs to be waterproofed with either tar or rubber membrane such as EPDM (Ethylene Propylene Diene Monomer) which are specially designed for this purpose.
What is EPDM Rubber?
EPDM is the commonly used abbreviation for ethylene propylene diene monomer. It’s a type of man-made synthetic rubber different than natural rubber. Simply put, pure rubber ages and becomes easily damaged with changing temperatures. On the contrary, EPDM is able to retain its flexibility and endure decades of changing temperature extremes.
Flat Roof Construction
While most assume flat roofs to be completely flat, these roofs actually have a slight slope to them ranging from 1 to 10 degrees to help prevent water from collecting and causing damage. This equates to roughly 1/4 of an inch or more elevation per foot.
Unlike regular sloped roofs, flat roofs have different requirements and should be installed or repaired by trained professionals to ensure the job is done properly. It is a good idea to check the multiple layers under the EPDM rubber. A core sample taken during a thorough roof inspection can shed light on the general condition of the structure under the visible surface.
What Causes a Flat Roof to Leak?
The most common cause of flat roof leaks is a lack of maintenance. If you have experienced a lot of rain and then noticed signs of water damage such as mold or discoloration in the ceilings below the roof surface, there’s a good chance that your flat roof has been leaking for quite some time. If it has been a while since last maintenance or if you haven’t had coating put on, you could also have a leaky roof. A thorough roof inspection would be a good place to start in properly assessing the condition of your roof, potential problem areas, and the scope of work needed to address the current issues.
Flat roofs are built with a slight slope to help the water drain. However, with age, it may develop areas where water collects and pools. It’s important to regularly maintain flat roof for evidence of such pooling water. Usual culprits may include gutters, drains, and downspouts.
Even if the pooling water doesn’t progress to leaks, it may pose other serious problems. With time, the excess weight of the water, which most likely wasn’t accounted for when building the structure of the roof since it was designed with a slight slope to help drain the water, may cause the roof to start sagging. This will in turn lead to even more water pooling completing a vicious and worsening cycle.