If you know it’s time for a new shingle roof on your home, you may have heard that you can just put a new roof over the existing one.
But is this true? And if so, is it a good idea?
Good questions. In this article we’ll explain:
- When roofing over your existing roof can be a good idea
- When you should tear off your roof and start from scratch, instead.
Why installing new shingles over old shingles can be good
Let’s start with the good. Many Arizona homeowners with shingle roofs do decide to roof over their existing shingles because:
- Less expensive. You can save money because there’s no dump fee for removing your old roofing, and there’s no need for additional felt paper over the old roof.
- Less hassle. Installing a new roof over shingles takes less time than tearing off the old roof.
- Looks just as good and lasts as long. As long as it’s done right and under the right conditions, installing new shingles over old ones can last as long and look just as good as a complete re-roof.
- Has the same manufacturer’s warranty. Manufacturers will still warranty the roof for the same amount of time as a re-roof, as long as it’s done by a qualified installer.
- Can serve as added protection from storms. Assuming your old roof is in good shape, the additional layer can serve as added protection in case a top shingle gets blown off in a storm.
As you can see, there are many benefits to installing a new roof over your existing one, and we do many of these for Arizona homeowners. But there are also times when it’s not the right thing to do.
When tearing off the old roof is a better option
Even with all the benefits of installing new shingles over old ones, there are times when it’s better (or even required) to tear off the old roof and start fresh. Here are some reasons to do that.
There are already 2 layers of shingles on your roof
Most building codes only allow 2 layers of any type of roofing on your home. So if there are already 2 layers, the choice is made for you. You need to tear off the roof and install a new one.
Current shingles are curling or in bad shape
The new shingle roof should lay flat on your old one. But if the current roof is curling, this isn’t possible. You’re better off removing the old roof.
Your roof leaks when it rains
If your roof is leaking, it’s usually better to get rid of the old roof so you can find the source of the problems and fix them. Putting a new roof over a leaking roof won’t remove the leaks.
Your roof is soft and spongy feeling
If, when walking on your roof, the majority of it feels soft and spongy, you may have some problems with the underlying sheathing of the roof. To fix it, you’ll need to remove the existing roof.
Your roof can’t support the weight
Shingles might not seem like they weigh much, but the shingles needed to cover a typical 2000 square foot roof can weigh in around 5000 pounds. That’s more weight than a typical SUV. So make sure the underlying structure of your roof can support another layer before installing over your existing roof.
Get a free professional opinion
You don’t need to guess whether you should tear off your old roof or lay new shingles over it. Lyon’s Roofing offers free inspections where we’ll carefully check your roof’s condition and walk you through your options.
If you’re in the Phoenix or Tucson metropolitan areas and need a trusted Phoenix roofer, give us a call or contact us online.