Metal Roof Installed Over Shingles With 1 Board Underlayment

Asphalt shingles can weigh up to four pounds per square foot depending on the brand.

Metal roof installed over shingles with 1 board underlayment.

In some areas building officials only allow a re roof over one layer of shingles. Once again this is used on cold roof construction. Make sure the product is designed to be used under metal. Before you decide to install a metal roof over existing asphalt shingles you need to answer a number of important questions.

Be sure the larger edge is laid so that the small edge of the next panel will overlap it. How many layers of shingles are currently installed. This provides a couple of benefits. Metal roofing weighs less than one pound per square foot.

5install metal panels or shingles. As long as the plywood under the shingle roof is in good condition this way can provide many benefits. Otherwise you will need to remove the shingles. A metal roof is an alternative to a shingle covered roof but a metal roof can actually be installed over shingles.

Installing metal roofing over shingles is the best solution. If you don t want to take our word for it check with your local building department. Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof line. Most building codes allow you to install a metal roof over 1 2 layers of shingles but no more.

This is by far the most common way to install a metal roof. It s the simplest and fastest way to install a metal roof. Installing a metal roof on top of shingles can be done in three basic steps only 2 are required. 3 install 1x4 purlins down over the shingles before installing the metal roof the third way to install a metal roof over shingles is by applying 1x4 purlins over the shingle roof.

There are really two ways to install a metal roof over a shingle roof. Many metal roofing systems can be installed over 1 2 layers of existing asphalt shingles saving time labor and landfill costs. We recommend a polypropylene scrim reinforced underlayment made up of multiple layers. The metal used for the roof can be tin copper aluminum or steel.

The first way is to run new underlayment over the existing shingle roof completely covering the old roof. Install the roofing screws vertically along each rib in the panel. However you should only install a metal roof over shingles if you have less than four layers of shingles on the roof. Winter heating costs may be reduced thanks to a double layer of insulation.

The first one being that the new underlayment will act as a second line of defense in case water would to somehow get underneath the metal roof. A metal roof reduces cooling costs during the summer months because it can reflect the sun s rays. When choosing to install a metal roof homeowners need to take into account several trade offs involving cost and performance.