Metal roofing sheets have to be installed one at a time.
How to install a metal roof over existing shingles.
Drip edge or edge metal is a piece of metal that extends approximately 0 75 inch beyond the roof s edge to channel runoff into your gutters.
How to install a metal roof over existing 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.
You must put in a completely new underlayment over the existing shingles before you carry out any installation.
To install it slide the flat wide flange underneath.
Use 1 4 inch metal wood screws to attach the metal sheets to the wood slat board base.
Place a sheet from top to bottom on a section of the roof.
This is by far the most common way to install a metal roof.
This will help prevent water leakage and provide a buffer between the metal roof and the existing shingles.
As long as the plywood under the shingle roof is in good condition this way can provide many benefits.
In terms of aesthetics you need to be careful in terms of choosing your metal roof solution so that it will blend into your surrounding neighborhood.
Start with an underlayment over the existing shingles.
Also if the existing shingles on top are not level or in very poor condition you may need to put a layer of roofing felt down or wooden frame over the shingles before installing the new metal roof.
However you ll want to check with your local building department before you make any decisions.