A roof can only have one layover done.
Shingle roof lay over.
Shingle around stacks vents and chimneys as necessary.
Therefore if your roof already has two layers of shingles layered separately you cannot have a layover done on top of it.
Secure the shingle with nails one inch from each corner.
Overlaying asphalt shingles with a metal roof is a big no no.
Stack pipes vents and chimneys are surrounded with metal flashing laid over tar.
Then we ll look a lot more reasons why you might not want to do this.
When contemplating a new roof many people hope to simply do a shingle over and avoid the extra cost and mess of tearing off the existing roof and starting from scratch.
Using a utility knife remove the tabs from the shingles you will be using.
How to install a roof over an existing roof determine the feasibility.
A metal roof should always be applied after the old shingles are torn off completely and new synthetic felt paper is applied.
The roof should be in sound.
Since you do not tear off old roofing shingles a layover can be done much faster and it is supposed to be a cheaper alternative to complete.
Inspect the condition of your current roof.
The first shingle should be centered over the line that you marked with chalk.
The answer is yes you can lay new roof shingles over old ones.
It s good to know that you can only choose this option if your roof has not been overlaid previously.
Now that we ve taken care of the primary question at hand we ll consider a couple of reasons why you might want to do this.
In fact the only pro to a shingle over is it s cheaper and cleaner.
Step 5 lay the trimmed shingles.
Their representatives said absolutely not to overlaying shingles with a metal roof.
Multiple layers of shingles can make it difficult or impossible for the nails to penetrate.
The condition of the existing roof is critical.
If the structure can support the added weight a typical 20 square 2 000 square foot reroof will cost at least 1 000 less than a tear off job.
Nail pieces of aluminum sheeting over holes that you can stick your finger through to protect roofing over holes from sagging dimpling cracking and leaking.
Although it sounds like a good idea we can assure you the cons heavily outweigh the pros.
I got this directly from the 1 metal manufacturer in the us.
Most building codes allow two layers of organic or fiberglass asphalt shingles on roofs with a 4 12 pitch or less and three layers on steeper roofs.
An overlay roof occurs when keep your existing roof as is choosing instead to shingle on top of it.
Re roofing or layover is a process in which the second set of shingles is layered over an existing set of shingles on a roof without taking off the existing layer of old shingles on a roof.