As the days get shorter, there is an urgent need to finish up roofing projects in the northern climates before winter shuts them down – not to mention the pressure to close in the building so other trades can do interior work.
To minimize leaks and other unwelcome surprises, keep the roof in the best shape possible before and after the worst of winter hits.
Guard against Damage
Set up a meeting with the general contractor and other trades to address important issues. First, identify the most critical aspects of the project, such as boiler rooms or electrical installations. Prioritize each and protect them accordingly.
Discuss storage and roof access. If sheet metal will be installed by someone other than the roofing contractor, establish coordination so metal work is completed without delay.
Install roof drains and hook them up to the storm sewers before roofing starts. Set roof drains into a sump (a depressed area with thinner insulation) so heat from the building will melt ice and snow at the drain first.
Next, determine who will decide when a temporary roof is necessary. If these were not part of the original bids, prepare documents to cover the costs of installing and removing these membranes. According to McGraw-Hill’s Manual of Low Slope Roofing, temporary roofs are recommended when:
- There is mandatory in-the-dry work inside the building before the weather allows you to install a permanent roof system.
- You anticipate a long stretch of rain, snow, or cold.
- You need to store building materials on the roof deck.
- Trades other than the roofing contractor need to conduct a large volume of work on the roof deck.
Remember to protect all roofing materials from the weather during storage and handling. Any materials that are susceptible to water damage or moisture retention should be covered or stored in a dry location until you’re ready to install them. Likewise, identify moisture-sensitive materials and cover them with tarps or other water-resistant coverings. Make sure you protect any water-based adhesives or materials from freezing.
Guard against membrane punctures by specifying walkways around roof equipment, especially at roof hatches. Polyester-reinforced SBS cap sheets give outstanding puncture protection when used under sleepers on bituminous and modified bituminous roofs. Require anyone accessing the roof to sign in and document their presence to help eliminate puncture or abuse leaks.
Safety before Repairs
Generally, no one should be traipsing around on a roof in bad weather, but occasionally roof access is necessary. Single-ply membrane roofs can be very slippery when wet, and the lighter-colored ones won’t melt ice very quickly compared to a dark-colored roof.
With the introduction of roof-mounted photovoltaics, there may be only narrow paths to navigate the roof, increasing the possibility of falling.
HVAC maintenance or repairing rooftop equipment both present possible hazards, and if the repairs affect building operations, access to the roof will be urgent. Keep in mind that wind damage or falling ice may result in electrical hazards.
Insulated boots, helmets, and gloves should be on hand for the emergency crews. If they must head up to the roof to remove snow or ice, request that they use plastic shovels and try not to damage the roof membrane.
Repairs to the membranes may also be necessary. Some thermoplastic membranes (specifically, PVC or TPO) can be heat welded if they do need a repair. However, the heat welders require electricity, and wet cables can be a hazard.
You may be better off to make emergency patches with asphalt mastic or peel-and-stick membrane, even though the mastic will contaminate the patch areas and must be cut out and replaced when the weather improves. For smooth, exposed single-ply membranes, duct tape will provide temporary protection until the worst is over.
BUR and modified bitumen membranes can be patched with a torching grade of polymer-modified bitumen. If you’re planning this kind of repair, send your critical personnel to a Certified Torch Applicator Training Program (CERTA) course offered by NRCA or MRCA.
The easiest strategy of all: keep the drains clear of debris!
Richard (Dick) L. Fricklas was technical director emeritus of the Roofing Industry Educational Institute prior to his retirement. He is co-author of The Manual of Low Slope Roofing Systems and continues to participate in seminars for the University of Wisconsin and RCI Inc.