Winter Flat-Roof Drainage System Issues
Roof drainage is a concern any time of year, but in the winter the risk of leaks increases significantly. Drainage systems are the key to moving water off the roof and away from the building. If drain system components fail, the result can be disastrous. The following is advice from Jillynn Stevens for avoiding leaks and other related problems with your flat roof this winter.
Drainage System Components
The essential components of any flat-span drainage system include the roof drains themselves, the gutters and the scuppers (sometimes called scoopers or scoupers). Roof drains provide an internal means to drain water from a flat roof. Commercial or industrial gutters are similar (at least in theory) to residential gutters, but with increased scale and durability to match the building’s size. Scuppers, originally a tool for draining water from the deck of a ship, are essentially holes and spouts in the side of a building through which water may drain, pouring into gutters or directly onto the ground.
Potential Drainage System Failures
During the winter, freezing temperatures pose a great risk to internal drains and the development of leaks. Both roof and scupper drains may become clogged from leaves and other debris left over from Fall. If scuppers are blocked, water cannot drain. If roof drains become clogged, a real risk exists for the drain to burst, causing interior flooding. When either drain clogs, water may be diverted down another side of the roof, potentially entering the building around windows or other potential penetration sites. One final risk involves the freezing of clogged internal drains, with a subsequent burst pipe causing interior damage and flooding.
Maintaining Your Flat-Roof Drainage System
The most effective method for avoiding drainage system failures is to have your drainage system inspected twice per year, preferably in early spring and late Fall. Roof drain inspectors will check all drains and scuppers for leaks and blockages. The inspector will verify the correct attachment of drain covers, gutters and downspouts. The inspector will also check for gutter or downspout blockages. At the same time, your inspector will check roof seams, welds and all roof penetrations for potential leaks. Penetration sites may include vent pipes, HVAC unit mount brackets and skylights. Skylights, although not technically a part of the drainage system, are another source of frequent leaks due to worn seals and flashing. The inspector will look at all roof, wall and cap flashing as well as the actual roofing material itself. If dips or ponds have developed, rain or melted snow can collect in those areas, causing a variety of drainage problems.
A professional roofing contractor can repair any problems with the drainage system quickly and effectively. Areas of sagging or ponding, however, may indicate the need for a new roof or extensive repair. Trust the advice of your licensed professional roofer as to the most effective methods for keeping your flat-roof draining system in good working order.