A metal roof can be installed over a shingle roof but you ll need to make sure the plywood under your shingle roof is in good enough shape to handle a new metal roof over top.
Put metal roof on wet shingles.
This shortens the effective life of the shingles and can adversely affect the roof sheathing.
Some roofing contractors recommend reroofing with standing seam metal because the total roof weight is but a fraction of a standard asphalt shingle roof which helps preserve the roofing integrity.
As long as the plywood under the shingle roof is in good condition this way can provide many benefits.
This moisture can lead to mold and mildew forming underneath the shingles.
Yes you can install a metal roof over shingles.
However you ll want to check with your local building department before you make any decisions.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
This method has its benefits as well.
Aside from limited visibility especially during heavy rain the roof slope wet and slippery surface and the oncoming rain will heighten the chances of someone slipping and falling.
The second way to install a metal roof over a shingle roof is with the use of purlins or battens.
About prime roofing.
Shingles can slip off installing roofing shingles on top of a wet roof can make your new roofing materials slip off and become damaged.
Roofing felt applied over a wet roof deck or shingles applied over wet roofing felt traps a layer of moisture within the roof.
However you should only install a metal roof over shingles if you have less than four layers of shingles on the roof.
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.
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.
Otherwise you will need to remove the shingles.
Building officials in some areas will only allow a re roof over one layer of shingles while officials in other places may allow you to place the roof over two layers of shingles.
5install metal panels or shingles.
Install the roofing screws vertically along each rib in the panel.
Roof replacement is expensive.
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.
However before you decide on reroofing with a metal roof you have to keep in mind that there are specific conditions that make reroofing with a.