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Metal roofs are quickly gaining in popularity among homeowners. They’re no longer just a novelty and are often a popular choice when it comes to adding aesthetics to your home.
However, if you’ve already got an asphalt roof, it is understandable that you might balk at the idea of replacing your roof. Most people think that before metal roof installation can take place, the previous roof must be completely removed.
This is not necessarily the case.
It is fully possible to go ahead with metal roof installation without tearing out your existing roof. However, keep in mind that it can only replace an existing asphalt roof under certain conditions.
If you’re looking to roof over an asphalt roof with a metal roof, the asphalt roof should be nearing the end of its lifespan. Furthermore, the roof should be lying down flat – that is, there should be no lifted or cracked shingles, bumps, or blisters.
If these conditions are met, it is fully possible to go ahead with metal roof installation over an existing asphalt roof. Doing so is a good way to save on labor costs. While laying over an existing roof, you can save on the costs of tearing out the roof, installing new underlayment, and more.
Should You Install a Metal Roof Over An Asphalt Roof?
As mentioned, this installing a metal roof over an asphalt roof is possible. It is also a good way to save money.
However, that does mean that doing so is a good idea.
There are several reasons why this route is not always a recommended one.
Decking
The decking is the wooden boards that make up the frame of your roof. It is on these boards that the other components are installed.
When you replace your roof, the old roof is torn down to the decking. This allows the decking to be checked and repaired or replaced if necessary.
By installing a metal roof over an asphalt roof, you cannot inspect your decking and check on the integrity. If there are any unrecognized rotten boards, you risk severe issues down the line.
Leaks
Old asphalt roofs can start to get leaky. If you go ahead with metal roof installation on top of your asphalt roof, you are simply covering up the issue, not taking care of it.
This means that you risk water getting under the metal panels in the future. If this happens, it will run down the asphalt roof and continue to run until it starts to leak into your home.
This issue is a combination of problems from two different roofing systems. This means that it becomes very difficult to track and find the source of the problem.
If you have decided to install a metal roof over your old asphalt roof, make sure that your contractor checks the condition of your existing asphalt roof.
Roof Materials
An important part of replacing your roofing system is getting the chance to replace important parts of the system and the materials used to construct them.
For example, your roof’s underlayment is an important part of ensuring your decking stays dry.
When your roof over your asphalt roof, you are using the old underlayment from the asphalt roof. You don’t have a chance to replace and update it.
Roofing materials are not meant to last forever. By roofing over an asphalt roof, you might be extending the lifespan of these materials by longer than recommended.
Final Thoughts
If you’re choosing metal roof installation for your home, it is always a good idea to start from scratch with a new metal roof. If you’re looking to install a metal roof for your home, contact DKG Roofing at (940) 497-2833 for help. We’d love to help you in any way possible.
