In fact the only pro to a shingle over is it s cheaper and cleaner.
Shingle over shingle roofing.
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.
Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.
Overlaying asphalt shingles with a metal roof is a big no no.
No missing shingles no gaps no holes in the roof no soft spots because of water damage.
How to shingle over existing shingles and how to shingle a roof how to install roof shingles shingle layout lines h.
Secure the shingle with nails one inch from each corner.
Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load.
Although it sounds like a good idea we can assure you the cons heavily outweigh the pros.
Shingle a roof over existing shingles save 75 give or take.
Before you reshingle a roof read our step by step guide for adding new shingles over old ones.
That s also why building codes commonly limit re roofing to no more than two layers.
1st and foremost your existing roof needs to be in reasonable shape.
Continue this until the first row of shingles is complete.
Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros.
Their representatives said absolutely not to overlaying shingles with a metal roof.
Roofing second layer of shingles roofing.
To shingle on top of existing shingles there are a few things you want to make sure.
A metal roof should always be applied after the old shingles are torn off completely and new synthetic felt paper is applied.
All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof.
The shingle should also hang about a quarter of an inch over the roof edge.
The next shingle should be placed and secured beside the first one.
If the job is done correctly with the new layer of shingles laid flat over the existing shingles the old roof cushions the new one and serves as a secondary barrier should wind or water ever break through the new shingles.
The first shingle should be centered over the line that you marked with chalk.