Metal Roof On Top Of Asphalt Shingles

Can you avoid tearing off your old asphalt shingle roof by putting a steel roof over it.

Metal roof on top of asphalt shingles.

As long as the plywood under the shingle roof is in good condition this way can provide many benefits. Wood framework base for the metal but the way that we get around it with the steel roofing is to construct a wood framework of one by four s and then lay the metal on top of that framework. Metal roofs must be laid flat on a vapor barrier because steel will condensate if there s any air space underneath it. Both metal and shingle roofs are great options for your next roofing project.

So if your roof has two layers it may require a complete tear off even though steel is lighter than asphalt. Metal roof over shingles condensation. This is by far the most common way to install a metal roof. After all you ll be making a significant and long term investment.

It doesn t matter if the air space is a half inch or six inches because the condensation factor will remain the same. 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. Put the steel down directly on a vapor barrier. The second way to install a metal roof over a shingle roof is with the use of purlins or battens.

The purlins are screwed or nailed down to the roof deck depending on how the metal roofing manufacture has testing for their roofing panels and then the metal is installed to the purlins. Things to know about metal over shingle roof problems. Most codes now allow no more than two layers of roofing before requiring a complete tear off.