Asphalt roof shingles remain waterproof until they dry out.
Roofing 2 layers shingles.
So we ll start at the bottom of the deck and work our way up through all the roofing layers until we reach the shingles and sunshine above your roof.
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.
How to put on a second layer of shingles evaluate the job.
Asphalt shingles come in two major types 3 tab and architectural.
Another issue is that when you add in the second layer it can add extra weight to your roof.
Examine the existing roof.
Saving on the initial shingle installation doesn t solve the long term cost of adding a second layer of shingles.
3 tabs are less expensive but also less durable have lower wind resistance and have a flatter appearance.
Roofing layers from the framing to the shingles.
Two layers of shingles trap more heat which in turn damages the shingles and shortens the life span of the roof.
Make repairs before.
Before you start hefting shingles to the roof consider whether or not the project is worth doing.
The temporary savings you receive from adding a second layer of shingles does not outweigh the negative aspects.
There are some advantages to roofing over existing shingles says dale richards owner of richards roofing in troy michigan.
The second layer of shingles will trap heat which can result in the decomposition of both roof layers.
When it s time to replace the roof again and you have no choice but to start anew two layers is the maximum allowed in most areas you ll have to pay extra for the two layer tearoff and disposal.
This is especially true if you ve overlayed your new shingles on top of warped shingles.
For example there s a starter course of roofing shingles installed at the eaves before the roofing shingles you can see.
You are correct that second layers typically don t last as long as single layers.
Most shingle warranties do not apply when shingles are layered over existing roofing according to internachi.
The homeowner will have two layers of shingles protecting the roof and the home is less likely to have ice dams he says.
Shingles are the element that most homeowners are familiar with as it is the layer you can see from the outside of your home and it is an important aesthetic aspect.
Richards also estimates that the homeowner saves at least 1 000 in costs associated with removing and properly disposing of the existing shingles.
Before you add shingles over shingles you need to look at the existing roof to make sure.
This will force you to replace your roof earlier than expected.