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  • Installing shingles as a second layer, short term gain. Long term consequences.
Rick February 23, 2023 0 Comments
multiple layered roof



A common tool used by roofers is to lower your initial cost of your new roof isn’t always the best for the homeowner. Installing your new roof, over your old roof. Today’s article is going to cover the consequences of going that route and why we recommend not to take that option. Your home’s roof is the number 1 protector of your house. It protects your home from rain/elements getting in, it shields you from the sun and heating up your home. So we need to ensure that we give your roof the most optimal installation to keep it lasting you for years! ReRoofing is not selective to any particular area. We find them all over chicagoland.

If you choose to install a new roof onto the old, you’ll never know what’s going on with the decking/wood below the old roof. If there is a problem, and the wood has rotted out and needs to be replaced. You will never get a chance to find out. When a new roof is being installed the old roof is removed all the way down to the decking. This allows our teams a chance to inspect, re-secure or replace if necessary.

Heat. When you have an additional layer of shingles below your new roof, the heat that your new roof absorbs from the sun will then conduct to the shingles below. That heat is retained longer and is harder to release. Excessive heat and UV are detrimental to asphalt, dried out asphalt will crack over time and become a water incursion point. Because of the issues caused by the first layer, it has an average lifespan estimated reduction of 15-30%.

Warranty. Because we do not know what’s going on with the first layer of roof we cannot warranty someone else’s work. Whereas when you do a complete installation of a roof system you know its condition from start, to finish.

Weight. Each square (one hundred square feet) can weigh between 70-100 pounds. An average home is around 28 squares. 28*210lbs = 5,880lbs sitting on your roof. That’s a Toyota 4runner sitting on your roof!

Labor. The next time the roof needs to be replaced either from damage or aging out will come with a cost. Because there will be double the weight, it’s double the labor cost for the roofer and then some. And then the dumpster cost is doubled since twice the weight is getting dropped off at the dump.

So when you consider all these issues, is it worth the savings to add your new roof as a second layer?


Source: https://www.perfectexteriorsinc.com
Perfect Exteriors Inc, your Perfect choice in Roofing Contractors.
Servicing Aurora, Naperville, Hinsdale, Wheaton, Lisle and the rest of the Chicagoland area for over a decade!

(Photo Credit: Perfect Exteriors inc Instagram – Starts with cedar shingles, 3 rows of asphalt shingles, and two roof decks)

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