Most people would limit this practice to a total of two layers of shingles.
New roof or second layer of shingles.
Replacing a roof can be very expensive and exhausting at the same time.
Select a length of roofing nails that penetrates completely through the new layer of shingles existing layer and the wood roof deck.
The second layer is also more difficult to install properly compared to new shingles.
Since the roofer is able to identify and repair high risk areas a new roof offers better quality than an old one.
Adding this membrane isn t an option with a re roof and the extra layer of shingles offers little protection against ice dams.
Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros.
Re roofing may affect the warranty on the new shingles.
The standard practice was that you could install a new layer of singles directly over the old layer during a re roof.
How to shingle over existing shingles and how to shingle a roof how to install roof shingles shingle layout lines h.
Flashing around roof penetrations and sidewalls can be compromised.
Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.
If you have done some serious research on roofing then you have probably heard about adding a second layer of shingles on top of the old ones.
In this video we provide details on how to install roof shingles over existing shingles.
A roof is one of the most vital components of a house.
If you don t tear off the old layer you can t examine the decking.
Posted july 31 2018 by onpage marie.
We discuss the nesting method which helps minimize an uneven appear.
Roofing second layer of shingles roofing.
A new roof fixes existing issues and traps less heat than multiple layers which can cause shingles to break and curl faster.
Re roofing used to be pretty straight forward with 3 tab shingles.
Plus depending upon the size of your roof you ve added multiple tons of weight which could pose a big problem if there is significant snow accumulation.
Be sure to check with the shingle manufacturer regarding all warranty issues and installation requirements before re roofing.
Pros and cons of adding a second layer of shingles.