How many shingle layers are too many? Adam Vaillancourt Roofing Contractor MA has the answer.

Posted on June 21, 2013

Milford NH, June 21, 2013—Adam Vaillancourt Roofing Contractor MA ( notes that the right answer is that your home should only have one layer of roofing shingles. That means when the roofing company re-roofs your house, it’s best to remove all of the old shingles and underlayment, repair any rotted plywood or roofing boards and replace all flashing. Going down to the wood when re-roofing also allows modern, waterproof barriers to be installed to guard against ice dams and other forms of moisture intrusion. “It’s important to remember that asphalt roofing shingles are heavy and the longer the warranty, the heavier the shingle,” said Adam Vaillancourt, owner of Adam Vaillancourt Roofing Contractor MA. “Most communities have building codes that allow a roof to have two layers. Some allow three. But that doesn’t mean it makes for the best roof.”

If you do decide that roofing over the old roof is your only choice, keep in mind that a second layer of roofing should only be installed on a roof that has a first layer of flat roofing shingles. Your roofing company should replace damaged shingles before the second layer is installed. It’s also unwise to install a second layer of shingles over any roof that is already leaking. Applying a new layer won’t necessarily eliminate a leak.

Finally, installing more than one layer of shingles may void or reduce the roofing company warranty. One reason is because the new layer of shingles will expand at a different rate than the old shingles underneath. The result is bulging and uneven wear. “It costs more to remove and discard the old shingles,” Vaillancourt says. “But the added cost is well worth the effort since it means you’ll maximize the life of your roof, the warranty and minimize a litany of future roofing headaches.”

About Adam Vaillancourt and roofing snow removal NH

Adam Vaillancourt Roofing and Construction is family owned and operated and they have a service relationship that customers can believe in and trust. Providing the highest quality standards of craftsmanship in the most efficient and timely manner, Adam Vaillancourt Roofing has quickly earned a reputation as one of the leading roofing contractors in NH and MA. With more than 1000 NH roofs completed to date Adam Vaillancourt Roofing has built quality relationships with hundreds of homeowners and contractors. As a CertainTeed select shingle master company our customers have the peace of mind that they are backed by a multi-billion dollar company which has been in business since 1904. For more information, visit