Can You Have Two Layers Of Shingles On A Roof

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.

Can you have two layers of shingles on a roof.

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. Now for the why. This will force you to replace your roof earlier than expected. 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. As mentioned above homeowners are legally limited to two layer of roof 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. The second layer of shingles will trap heat which can result in the decomposition of both roof layers.

There are some advantages to roofing over existing shingles says dale richards owner of richards roofing in troy michigan. If you don t tear off the old layer you can t examine the decking. If there is one thing that i love about my industry it is that things are constantly changing. This is especially true if you ve overlayed your new shingles on top of warped shingles.

Richards also estimates that the homeowner saves at least 1 000 in costs associated with removing and properly disposing of the existing shingles. By not removing the first layer of shingles homeowners would be able to save on labor costs and shorten the time frame of the job. Most people would limit this practice to a total of two layers of shingles. The main case for adding a second layer of shingles is simplicity.

The taylor made team. The standard practice was that you could install a new layer of singles directly over the old layer during a re roof. Affects inspection reports. And roofing guidelines are no exception to the rule.

Another issue is that when you add in the second layer it can add extra weight to your roof. Any more than that and you d have to tear off the old shingles before installing a new layer. Therefore if you already have two layers you ll need a full tear off. Most building codes allow two layers of organic or fiberglass asphalt shingles on roofs with a 4 12 pitch or less and three layers on steeper roofs.

In fact the extra layer can reduce your roof s lifespan by up to 40. Reasons why you should not add a second layer of shingles it will shorten the lifespan of your roof.