Can you roof over dimensional shingles

Adding this membrane isn't an option with a re-roof, and the extra layer of shingles offers little protection against ice dams. Re-roofing may affect the warranty on the new shingles. Pretty self-explanatory. Be sure to check with the shingle manufacturer regarding all warranty issues and installation requirements before re-roofing. Local codes might not allow re-roofing.

Two layers is the maximum in most areas, but some building codes allow only one. For example, towns in climates with heavy hailstorm activity or significant ice dam problems may not allow multiple roofing layers. A re-roof might not look good on an inspection report. Adding new roof shingles over old ones is tempting to a lot of people planning to sell their house in the near future: why pay for a tearoff if you can get away without it?

Of course, it'll be the new owners who are stuck with the extra expense of a two-layer tearoff down the road, along with any problems arising from an improper re-roof job.

Because of this, home inspectors often report double-layer roofs when they find them, and they may warn the buyers of potential problems associated with re-roofs. Contact a reliable roofing contractor to discuss your options for roof repair or replacement. Philip Schmidt writes for Networx. Looking for a Pro? Call us at Philip Schmidt. Get Free Quotes. What sets us apart from other contractors? Our business was born out of a dedication to outstanding workmanship and to the people and communities we serve.

We have roots in the local area and a connection to other residents and business owners. When you hire us for roofing work or other projects, you can count on the kind of customer service that makes you feel welcomed and heard. We offer personal attention, prompt response times, and a dedication to your needs and preferences. Integrity is our core principle, and it gets expressed in multiple ways. It emerges in the demands we make on our abilities and the high standards to which we hold our work.

We honor our commitments and have cultivated a reputation based on successful projects and profound respect for people. There are 2 reroofing application techniques we want to highlight: bridging and nesting. The bridging method allows the new course of roof shingles to overlay 2 or 3 courses of the existing roof shingles. This method usually allows for the proper exposure of the roof shingles and is commonly used when applying metric-sized roof shingles over English-sized or over wood shingles.

Telegraphing or telemarking means that the old layer of old shingles can be visible in the new layer of shingles installed. Nesting minimizes the uneven appearance of the roof when compared with bridging over existing roof shingles. Installation using this method may shorten the roof shingles exposure and uses more roof shingles.

The nesting method butts the top edge of the new roof shingle to the bottom edge of the existing roof shingle. Try fitting the new roof shingles into the existing layers prior to deciding whether to use this technique. The existing exposure the exposed part of the roof shingles mainly determines what the new visual part will be. Reroofing is a great option for those who have a generally good roof which is at the end of its life cycle or a roof that is slowly losing its function. As opposed to a roof replacement, it does not involve tear off, which means that it reduces both time and cost for the project.

It is always a good idea to consult with a roofer you trust, who can do an inspection, give you an accurate estimate, and who will advise you on what the best option is for you. If you are a roofer , don't miss any of our updates! First name. I agree that my personal data will only be used for sending the newsletter. I can unsubscribe the newsletter any time. I agree with the IKO privacy policy.

Breadcrumb Home Blog Reroofing over an existing shingle roof: Some need-to-know facts. Renovation Application FAQ. The condition of the existing roof structure must be strong enough to support the additional load of roof shingles. The overall appearance of the roof must be flat. If sagging is visible, there might be structural problems needing to be fixed. Split and nail flat all buckled, raised tabs and curling roof shingles. Nail warped decking material if necessary. The fastening anchorage for the nails in the new roof shingle layer must be tested.