Storm Readiness for Commercial Roofs: Five Things to Know

With storm season upon us, CRE owners and facility managers may find themselves acutely aware of the state of their roofs. Hopefully, you have a comprehensive Roof Management Plan in place to protect the most expensive system in your commercial building and reduce the likelihood of leaks. Even so, a bit of understanding and preparation can go a long way in minimizing and managing the impact of heavy rains at your properties.

1. Proper Drainage is Priority #1. During any rain, thousands of gallons of water are running across your roofs. Because your roofs have a “low slope,” it is very important that water reach the drains and evacuate as soon as possible. If you observe water exiting the roof via overflows and running down the walls on the exterior of your building, it may mean that the primary drain in that area is not operational or that a downspout is blocked. This condition has first priority and should be reported to your roofing consultant immediately.
2. Wind + Rain = Water Entry. Storms may have winds as high as 15 to 35 miles an hour and, while the roofing membranes on your buildings are watertight, every HVAC unit, vent, stack, louvered skylight and penetration is not. These rooftop penetrations are designed for rain to come straight down or at a slight slant. Intense wind will blow the rain sideways, not unlike taking a fire hose to every opening on your roof. If you observe water entering via these openings during a storm, you most likely have a one-time leak that cannot be serviced. Water entering via the fresh air intake of any HVAC unit is also a possibility, especially if the unit is shut down and there is no pressure in the unit.
3. Take measures to reduce interior damage. In each building and/or office, locate your HVAC registers. If there are computers or anything of value under these registers, move them. Likewise, if you have warehoused product that is under any type of venting, register, or louvered skylight and the product cannot be moved, find some way to cover it.
4. Know where the leak is coming from. It may sound obvious, but roofing contractors are often called for leaks coming from windows, doors, walls or under the foundation. Pay attention to where water is entering the building so you can engage the appropriate contractor to repair the leak. After a major storm, contractors are in high demand, so calling the right professional the first time can expedite the remediation process.
5. Be prepared to wait out the storm. If you have a roof membrane leak, remember there is very little a roofing contractor can do if it is raining hard or the roof is very wet. Available materials are very limited and getting something to stick through water is close to impossible—this is why proactive roof management is so critical to mitigating property damage. Once the rain has subsided, a proper repair can be made. Most importantly, please remember that during a storm, particularly if the winds are strong, it is not safe for anyone to be on a roof. Never send staff or a contractor onto a roof to inspect during severe weather.