Unknown to many, the roofing system contains several parts that make protecting your home from weather all the more effective. One important but often overlooked section is the drip edge. Today, let’s learn more about it and how it keeps your home safe from water damage.
What is a Drip Edge?
A drip edge is very useful to stop water from being able to seep under the edge of a roof deck. Without a drip edge the edges will rot all the way into the frame studs and sheathings. This will only take about 15 years for it to happen. If it does, you are in for some serious repair work. To avoid those problems it’s best to install a drip edge early on. Source: DoItYourself
Where to Install?
Obviously, the most critical location for drip metal is precisely at the site of the majority of drips, the eaves! Rake edges should also get metal edging, but it is just not as critical. And the installation sequence of the edge metal with the felt underlayment is optional in most manufacturers’ printed instructions. You can install the felt either on top of or below the edge metal. And since water travels somewhat parallel to the rakes, this does minimize the need for coverage.
However, the edge receiving the most water on a steep-sloped roof needs the best protection affordable. If the shingles extended more than 3/4 to1-inch over the edge, they tend to bend, eventually fracturing along the edge of the roof deck below. If the metal edging is left off, this decreases the chance for all of the water cascading over the eaves to make it into the gutters, if indeed there are any. Otherwise, shingles breaking along the line of the roof deck allow the possibility of water getting into the substrate by turning back up under the bottom of the shingle. The harmful effects of this condition are exacerbated when the underlayment is not fully extending over the edge and/or if the fascia board is not flush with the lower edge of the wood roof deck.
Many times the roof deck is installed early on in the project and covered with felt in order to dry the house in and speed up the interior work below. Roofers will hurriedly run a cutter along the edge of the wood deck, but rarely do it in a straight line. This leaves the edge of the felt somewhat short of the edge, thereby failing to overhang the roof deck. It only gets worse when the (usually 3/4-1″ thick) fascia board is added later when the finish work is being done. This makes the felt edge that much farther from the true drip edge. Source: Improvenet
How to Install?
Slip the wide, flat flange of the material all the way under the first course of roof shingles, as illustrated. Make sure the outer edge extends over the gutter. If it doesn’t, pull the drip edge out slightly from under the shingles.
Secure the drip edge with roofing cement. Apply a continuous bead of cement along the top of the drip edge, then press down on the shingle. If necessary, secure the ends of the drip edge with short roofing nails; just be sure they’re positioned high up under the shingles. Source: ThisOldHouse
Contact:
Kerrisdale Roofing & Drains Ltd.
168 W 71st Ave, Vancouver, BC V5X 4S7
(604) 360-2114
