Can You Roof Over Existing Shingles?
Updated: May 11, 2021
I get a lot of the same repeated questions from customers. One of the most common questions I get asked is “Can you roof over my existing shingles?”
This question usually comes from a homeowner looking to save some money by reducing the workload required of a re-roof. As a homeowner, it’s always nice to save money on home improvement costs. But when it comes at the expense of your greatest investment, you should think again.
Laying asphalt shingles over the existing shingles is referred to as a shingle over. Rather than tearing off the existing shingles, a shingle over avoids the extra cost and mess of tearing off the existing roof and starting from scratch.
This might sound like a good idea, but I assure you the cons outweigh the pros. In fact, there’s only one benefit to a shingle over: it’s cheaper and cleaner.
4 problems with a shingle over
A shingle over might be faster and cleaner. But what if there is an unknown leak or bad roof flashing? You won’t be able to repair it during a shingle over.
Let’s take a look at the four reasons you should never roof over existing shingles.
1. A shingle over doesn’t allow the shingles to lay flat
Shingles must be laid as flat as possible to be effective. Old shingles are often lifted or curling, making a reroof a better choice.
2. A shingle over adds extra weight to the roof
Shingles add weight to roofs. In fact, every 100 square feet of quality roofing adds 350 to 450 pounds of weight. Two layers of shingles place unnecessary stress on your roof.
3. A shingle over doesn’t allow you to inspect what’s underneath
A tear-off allows you to inspect the underlayment and decking. You won’t be able to identify any problems if you shingle over your existing shingles.
A tear-off allows you to find a potential leak or any other problems that could be overlooked with a shingle over. This could lead to even larger, more expensive repairs in the future.
4. A shingle over can void warranties
Re-roofing may void warranties or create problems come inspection time. A home inspector will report a shingle over to any potential buyers.
I understand that you may want to replace your roof for the lowest price possible if you’re planning on selling your home. But inspectors will notice it and will report it to any potential buyers who have an inspection performed. The last thing you want is a failed inspection while you’re trying to sell your home.
Roofing over your existing shingles may sound like a good idea at first. But saving a few bucks at first just isn’t worth it. A shingle over can lead to more costly repairs down the road.
My advice to you is to do it right the first time. If you have any questions about a new roof, contact JB Roofing for a free assessment at 515-554-1964.