Asphalt Shingles Roofing And Flashing Details

Asphalt Shingles Roofing And Flashing Details

In our previous discussions about roofing in Tucson, we’ve looked at the three types of valleys: woven, closed, and open. Now let’s look at the two types of flashing: step flashing and L flashing. When the roof planes butt against vertical walls or chimneys, metal flashing must be placed over the end of each course. This procedure is called step flashing. In this situation, step flashing performs better than solid continuous flashing, because it ensures a waterproof seal with these critical areas.

The use of continuous flashing or L flashing at these areas is not recommended, because this flashing is dependent on sealants for water tightness. Overall, step flashing is the most proven way to flash these areas. The metal flashing strips used for step flashing are rectangular. Typically, ten inches wide and two inches longer than the non-exposed area of the roof shingle. For typical five inch shingle exposure, use a ten inch by seven inch piece of flashing.

GAFL has several shingles that are much wider than standard shingles. These shingles measure seventeen inches by forty inches long. The non-exposed area on these shingles is typically nine and a half inches wide. To completely cover these shingles with step flashing, use ten and a half inch wide flashing or simply install two pieces of a normal step flashing to fully cover this area. Another question is whether to use new step flashing or to reuse the old step flashing.

Many times it can be very difficult to install new metal step flashing on a home where there is painted siding or masonry siding in place. GAFL recommends to only reuse existing step flashing if it is in like new condition. Like new means it is not buckled, rusted, bend, cracked, or broken. In all cases it is best if possible to install new step flashing. Installing step flashing at sidewalls is required on Golden Pledge Installations. If reusing old step flashing, it must be in like new condition.

Bend the ten inch length, so that it extends five inches over the roof deck and five inched up the wall surface. Place the first step flashing over the end of the starter course shingle and position it so that the tab of the end shingle in the first course covers it completely. It will help if you keep in mind that all components of the roof system are assembled so that the water will be shed down the slope of the roof. Secure the step flashing to the roof with two nails.

Don’t nail through the flashing to the wall because the flashing needs to be able to move with any deck in building movement. Fastening it to both might cause it to tear, if the building moves or settles.Next, apply the first course of shingles up to the wall and position the second flashing strip over the shingle. The non-exposed area of the shingle in the second course should be completely covered. Mail the step flashing to the roof. The second course of shingles follows.

The end is flashed as in the preceding course. Continue this process to the top of the roofing area. On a vertical sidewall, the siding may serve as counter flashing over the step flashing or a separate counter flashing may be used. You’ve seen how the step flashing is used. Another problem location on the roof is where the roof meets a vertical wall. This is where L flashing is used. Let’s look at the recommended way to apply a finish course of shingles on the roof where it meets a vertical sidewall. Shingle up to the wall. Lay a bead of plastic cement at the top portion of the shingle.

Place the L flashing over the shingles and under the siding. Remember that everything is designed to shed water from the counter flashing of the siding to the shingles under the L flashing. When the shingles are run all the way up to the wall, nail the flashing into the deck, but not into the vertical wall. You can seal the nails here or run a course of shingles over the metal and embed them in a bed of asphalt cement. When applying shingles around all vent stacks, here are some important steps to consider.

Apply a piece of Weather watch or Storm Guard, approximately two times the size of the flange on to the deck protectors, under the shingles. Seal to the pipe sides.Installing Weather Watch or Storm Guard around pipe flashing is required on all Golden Pledge and Systems Plus Ltd. Warranty Installations. Trim the shingle to fit and check shingle alignment. Apply asphalt cement under shingles, around the vent stacks. Set the shingles into the cement. I always replace all flashing. In my opinion, trying to save a few bucks by reusing flashing is just not worth it.

Another key component of the weather stopper roof system is the hip and ridge cap shingle. Nothing dresses up a roofing job more than a neat hip and ridge installation. It is the crowing touch of the roofing job. But hip and ridge shingles are more than just a good looking finishing touch. This roofing business can be really crazy. Every day I see roofers who sell a property owner a 30, 40, or 50 year shingle and then they finish the job by using a 20 year regular shingle for the hip and ridge cap. Isn’t that just a flat out rip off? The customer paid for more than 20 year performance and what do they get? A twenty year roof!

GAFL certified contractors are professionals and should use the right hip and ridge product, like TimberTex or RidgeGlass for a great looking job. Let the trunk slammer install install cheap hip and ridge. Professionals do it right. GAFL also makes shingle match – a specialized paint that can make unsightly vent and accessories blend in with the color of the roof.These finishing touches can make a great looking roof. It’s what the property owner deserves. Next, we’ll look at some advanced roofing materials.

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