5 Reasons You Shouldn’t Mix Old & New Shingles When Reroofing

Worthington home new roof

When it comes time for a new roof, it may seem logical to just lay down a layer of new shingles over the old ones to save yourself the time and money of a tear-off. However, while there may be some short-term savings, mixing old and new shingles comes with a whole slew of long-term negatives.

Roof Repair

• Layovers can void or significantly reduce the warranty. Installing more than one layer of shingles adds additional insulating layers to the roof. Because heat becomes trapped between the shingle layers, this process will shorten the life of your shingles and cause them to curl. For this reason, manufacturers will not warrant a roof with more than one layer. Also, with dimensional shingles over the old, you won’t get a good seal with the new shingles. This is due to the uneven surface which doesn’t allow for proper seal strip connection.

• You can’t inspect for damage. Not all leaks are visible from inside a home. Layover roofing in Delaware, OH, prevents our roofers from being able to check the roof deck for rotten or damaged wood. Leaks will also be harder to track through more layers of shingles.

• You can’t upgrade your underlayment. There is no way to install new ice guard, new eave metal or new flashing assemblies without tearing off the old roof.

• It will cost you more money down the road. Some homeowners make the mistake of buying cheap new shingles to lay over the old ones. What they don’t realize is that 10-15 years down the road, when their roof fails, they will have to pay considerably more to have the old roof ripped off and disposed of because of the extra layer.

• Weight can become an issue. Multiple layers of shingles are extremely heavy, putting stress on the underlying roof framing. This can be a problem for older houses which often do not have the structural integrity needed to bear the added weight.

Muth & Company Roofing, one of the leading Columbus roofing contractors, recommends doing a full removal of old shingles before laying down high-quality new ones. This will allow you to get the maximum amount of life out of your roof and receive all the benefits of your warranty. Contact us at (614) 682-3060 for more information and a FREE quote!

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