Your roof isexposed to the elements and is subject to wear and tear, so even if you do your part to make needed repairs, the time will come when you need a whole new roof. At that point, most roofers recommend a “tear off.” A “tear off” means removing everything down to the plywood decking before having new roofing materials added on.
Why Choose A “Tear Off” Before Getting A New Roof In Kitchener
The “tear off” process is more expensive than attempting to lay new shingles on top of the old, but it will save you money in the long run. Even if your roof is not leaking, there may be problem areas under the shingles that need attention. The last thing you want to do is put thousands of dollars of new roofing products atop a weak structure and old materials. Opting for a tear off will decrease your chances of having problems with the old, underlying shingles. This is why most good roofing contractors recommended a tear off when installing a new roof, even if local codes permit adding an additional layer of shingles.
What Can Happen If You Lay New Materials Over Old
Here are a few specific problems that can result from laying new shingles on top of old:
- Your roof is built on decking that is usually made of plywood. Once the wood is exposed to moisture either from a leak or even from moisture buildup, its structure can be weakened. Sometimes this is obvious; you might see sagging in the attic or your roofer might feel weakness when walking on the surface. All too often, once shingles are removed, the plywood shows many more signs of deterioration than you may realize.
- An effective roof requires not just a sturdy underlayment and solid shingles, but it also requires that the flashing around chimneys, roof vents, roof angles, wall intersections, and roof edges are in good condition, with no signs of rust or other deterioration.The flashing is usually not addressed if the existing shingles are not removed and will continue to deteriorate with time and exposure.
- A tear off ensures that you will have new installation of all the components needed to protect your home from water, such as a new ice/water membrane and felt underlayment positioned between the shingles and the plywood decking.
- Aside from protection, getting a tear off controls the weight your roof has to bear. In the past, roof trusses were required by code to be made of 2×6 boards with cross connecting rafters on a half-inch base of plywood. Current codes in many areas only require 2x4s, which are less able to support the weight of an additional layer of shingles. Just 100 feet of shingles weighs 200 pounds or more, so your 2,000 square foot home might be supporting 4,000 pounds of shingles. That amount may double with another layer of shingles. A winter of heavy snows can add even more weight and contribute to a possible collapse.
- Since your roof is exposed to the elements, it becomes a repository for dirt, bacteria, and algae. This is a normal development, but when you add a new layer of shingles, you are trapping years of old buildup that could shorten the life of your new roof. Some roofing material manufacturers may limit their warranties if you install a new roof over old shingles.
Your New Roof Is An Investment, Protect It
Reroofing over old materials may save you the initial cost of labor and disposal, but it will undoubtedly cost you in the long run. When you’re ready for a new roof in Kitchener, contact The Roofman. They believe in installing roofs right the first time. Call them today at 519-744-3830 or submit a website form to inquire about a quote for a new roof in Kitchener.