Before an overlay is considered it is vital that you understand that an overlay must be done to the entire roof not just parts of your roof.
Roof life on an overlay.
Because of the possible drawbacks of overlay structural problems mainly local building codes may not allow for the overlaying of a roof.
An overlay isn t always possible.
A roof overlay is the process of adding a layer of shingles and waterproofing over a preexisting roof.
When it s deemed practical a lot of localized repairs to the old roof are often done so that a solid foundation is provided for the new roof.
The design of re roofing specifications follows the same principles as that of new work but there are added complications arising from the need to adapt reuse or overlay existing materials.
An overlay roof or the act of overlaying a roof is when your roofer puts a second set of shingles directly on top of your existing roof.
While this isn t the most common method of roofing it does happen especially when homeowners are hoping to save a bit of money on their overall roofing costs.
An overlayed roof will also have a shorter life span than a roof of the same material that is applied after a tear off.
This isn t perfect though.
If the existing roof has decayed sufficiently it s just not done.
Find a quality roofing contractor who can assess your roof s condition and do the job correctly.
Beveled wood pieces called horsefeathers must be laid along the thick edges of the shakes to make a fairly flat surface.
It is most commonly used as a way to extend the life of a roof and save money by not paying removal and disposal costs of the old roof.
More problems with overlay.
The double roof will trap extra heat which can warp and otherwise prematurely age the new roof.
Before you reshingle a roof read our step by step guide for adding new shingles over old ones.
Asphalt shingles can be laid over cedar shakes or shingles however this is a roofing project best left to pros.
When renewing an existing roof consideration should be given to whether or not the thermal performance of the roof should be improved and the impact that may have on detail work particularly abutments.
Another possible issue with overlaying your roof rather than replacing it is that your local government may not allow such a practice.
An overlay may also be an option for roofs with minor leaks.