Guide for Rubber Roof Installation over Shingles
Rubber roof installations are rather easy and a great roofing option. A rubber roof provide a number of benefits that are unavailable from other roofing methods. First, rubber roofs are less expensive to install. Many actually come with warranties up to 45 years; therefore, the cost advantage over time is even greater. Rubber roofs help to keep your home warm if you live in a cold climate and cool if you live in a warm climate. Rubber roofs are able to absorb or reflect sunlight and have been proven to reduce the cost of heating or cooling your home. Rubber roofs, unlike other methods, are easy to install and most residential jobs can be done by the average do-it-yourselfer.
Rubber roofing cannot be applied directly over shingles. If you don’t want to do a complete tear off of your existing shingles, you have to consider a number of factors. First, re-roofing is allowed in most jurisdictions; however, re-roofing over more than 1 layer is often prohibited. Check with you local authorities and find out how many roofing layers you already have on your home. Next, consider the weight of the current roof. If you notice things like sagging decking or buckling framing, applying a rubber roof over shingles may not be the best bet. Though rubber roofing is not terribly heavy, applying it over an already weighty roof system may prove deleterious in the future. Last, rubber roofing must be provided with a barrier between it and the old roof. It cannot be adhered directly to asphalt. Therefore, you will have to secure some plywood, OSB board, or polyisocyanurate atop the shingles before proceeding.
Step 1—Clean the Roof Undersurface
Whatever surface you have chosen to lay atop the shingles has to be clean and dry. Make sure that there are no sharp edges or debris left on the barrier surface. If you are using plywood, it is best that it has been lightly sanded and wiped with lint free rags. This will ensure that the membrane doesn’t become damaged and leaves the boards dust free.
Step 2—Apply Adhesive
Lay the rubber out in largest size you are comfortable working with. The small number of pieces creates the smallest number of seams. Having fewer seams is beneficial because it is at the seams that water is able to penetrate the roof as it ages. Once the rubber has flattened out, apply adhesive to the barrier substrate and the membrane.
Step 3—Secure Membrane
Once the adhesive has become tacky, stick it down. Make sure that there are no ripples in the membrane. Once the entire piece is attached, sweep over the section with a push broom to ensure proper adhesion.
Step 4—Tape Seams
There will be overlap between adjacent pieces of membrane. Apply seam adhesive to the top piece of membrane to secure to the bottom piece. Once the adhesive has dried, roll the seam tape over the seam. Make sure that the tape is wide enough to offer adequate coverage on both sides. Use the silicone hand roller to secure the seam even further. For additional seam protection, clear caulk can be applied to the edges of the seam tape.
That’s it! You have just applied a completed a rubber roof installation. Your home is now secure from water damage and extreme weather for years to come.