Drip edge and rake edge are not required by Alberta building code nor by manufacturer specifications on roofing systems; however, virtually every responsible professional roofer in the Alberta roofing marketplace will recommend having it installed. It doesn’t cost much and it serves an important purpose.
Drip edge goes along your eaves trough areas and rake edge goes along your gable ends. They both look very similar and are often not differentiated in name by some suppliers and simply called drip edge. There is a slight difference in reality though, as the angle of the two metal component act in a specific way to shed water from the roof deck.
Because the Alberta Building Code does not require the installation of Drip edge and rake edge, many new homes and/or low budget roof systems do not have drip edge installed in order to fill the demand for economical housing. Here, at The Roof Hospital, we always recommend for drip edge and rake edge to be installed on every roof system – no matter what.
The function of this component in your roof system is pretty straight forward; it protects your roof deck from exposure to weather. In your eaves troughs, snow and ice build up in colder weather and can work backwards, up under your shingles, soaking into the wood framing, which can eventually lead to wood rot and deterioration. On your gable ends, driving winds can force moisture sideways under your shingles, which creates a similar end result; rotting wood.
Drip and rake edges are available in a variety of different colors and sizes and can be custom built for the needs of your roof system. Installing an appropriate drip edge often saves hundreds and sometimes even thousands of dollars when your roof system needs to be replaced.
Typical pricing for drip edge and rake edge comes in around $1 – $2 per linear foot.
Standard sized drip edge and rake edge are approximately 4 inches in total length, with about ¾ inch bent at an angle to hang into the eaves trough or overtop your gable facia. The remaining length laps onto your roof deck and fastens in place using appropriate residential roofing fasteners, such as a 1 ¼ galvanized pneumatic nail with a flat head, designed for residential roofing applicators and available from local suppliers or hardware stores.
Your best drip edge and rake edge, as per the Alberta Roofing Contractors Association’s Good Roofing Practices, will overhang plywood into your eaves trough by approximately 1.5 inches and over your facia at the gables by approximately 1 inch.
In conclusion; drip edge and rake edge is a piece of metal which covers the perimeter of your roof deck plywood to protect it from being exposed to weather, such as snow, ice and wind driven rain. It is low in cost, high in effectiveness and overall recommended on all Alberta, and particularly Calgary, based roofing systems.