For dimensional shingles being installed over a layer of existing dimensional shingles you should always use a 1 1 2 inch roofing nail.
Roofing shingles over old.
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.
Damaged decking will need to be repaired before you can install any new shingles.
Although many metal roof systems can be applied over an existing roof layovers are more commonly done with asphalt shingles.
In fact the only pro to a shingle over is it s cheaper and cleaner.
Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.
All shingle manufacturers honor the warranty whether their products are used for a reroof or a new roof.
Choose a shingle style with the same dimensions as those on your.
Damaged shingles should be removed to check the decking for problems.
Manufacturers will still.
Looks just as good and lasts as long.
Installing a new roof over shingles takes less time than tearing off the old roof.
As long as it s done right and under the right conditions installing new shingles over old ones can last as long and look just as good as a complete re roof.
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.
Adding new roofing over old sometimes called a re roof is possible only with asphalt shingles also called composition shingles.
Step 3 cover the old shingles.
But before we get started one thing must be clear.
Install a layer of roofing felt over the roof before you begin installing the new shingles.
Before you reshingle a roof read our step by step guide for adding new shingles over old ones.
The felt should be secured every six inches with nails or staples.
Although it sounds like a good idea we can assure you the cons heavily outweigh the pros.