Can You Have Two Layers Of Shingles On A Roof

The standard practice was that you could install a new layer of singles directly over the old layer during a re roof.

Can you have two layers of shingles on a roof.

The main case for adding a second layer of shingles is simplicity. In fact the extra layer can reduce your roof s lifespan by up to 40. If there is one thing that i love about my industry it is that things are constantly changing. Reasons why you should not add a second layer of shingles it will shorten the lifespan of your roof.

Therefore if you already have two layers you ll need a full tear off. Richards also estimates that the homeowner saves at least 1 000 in costs associated with removing and properly disposing of the existing shingles. Any more than that and you d have to tear off the old shingles before installing a new layer. The short answer is yes.

Now for the why. When i started my real estate career i sold homes with three layers of roofing. As mentioned above homeowners are legally limited to two layer of roof shingles. For a second layer to be as good as a roof tear off you would have to have sound decking no leaks and a roof with no sidewalls where flashing is needed in order to tie the tiles in to the exterior walls.

Having multiple layers of shingles is going to make your roof hotter because the heat gets trapped between the layers which could mean premature aging of the shingles. This is especially true if you ve overlayed your new shingles on top of warped shingles. Additionally if your roof is severely damaged it likely won t be able to support the weight of a reroof and will need to be torn off. 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.

And roofing guidelines are no exception to the rule. Though both these points are valid you will end up spending the same amount of money or more later to have two layers of shingles removed. Affects inspection reports. If you don t tear off the old layer you can t examine the decking.

This will force you to replace your roof earlier than expected. Another issue is that when you add in the second layer it can add extra weight to your roof. The taylor made team. There are some advantages to roofing over existing shingles says dale richards owner of richards roofing in troy michigan.

Most people would limit this practice to a total of two layers of shingles. The second layer of shingles will trap heat which can result in the decomposition of both roof layers.