Many people are moving to metal roofing for their homes. This is because of their numerous advantages such as extra protection, energy efficiency, and long-lasting nature. When you decide to switch to a metal roof, a common question is if you can install it over pre-existing shingles.
The answer is almost always yes, you can install a metal roof over an existing shingle roof. One of the many reasons metal roofs are becoming more popular is that they don’t require entirely pulling off the old roof, which is a time-consuming and costly task.
Metal roof, despite its extreme strength, is extremely light, it weighs less than a pound per square foot compared to up to four pounds for asphalt shingles. The overall weight that the home structure must carry does not rise much when a metal roof is installed over existing shingles.
Installing a new metal roof over an existing roof not only saves money by avoiding the cost of entirely replacing the old roof, but it also provides more insulation above your home, preventing heat and cool from escaping.
Since we’re on the subject of insulation, we should also emphasize that metal roofs are heat-blockers, meaning they reflect heat rather than absorb it. As a result, the additional insulation provided by your shingle roof will not act as a heat trap for heat escaping through your metal roof.
Factors to consider before installing a metal roofing over shingles
When installing a metal roof over shingles, there are a few things to keep in mind.
In the vast majority of cases, everything we indicated regarding placing metal over shingles is correct. However, it’s always a good idea to double-check with your local building agencies to ensure that metal-over-shingle installations are permitted.
If you have a shingle roof that is leaking, look for rotten rafters or sheets. These issues should be addressed prior to the installation of the new roof. If the current roof’s weight has produced structural issues such as sagging decking or buckled trusses, these issues must be addressed before the new roof is installed.
To prevent the granules from contacting the metal and causing corrosion, it’s usually a good idea to install some form of underlayment on top of the shingles. This is something your metal roofing contractor will discuss with you.
There you have it! Metal roofing has several benefits which include lower cooling bills, low maintenance, durability, and protection, You can install a metal roof over your shingles after confirming that everything is fine.
