Why Not To Add A Second Lkayer On A Roof

You re essentially adding a second roof on your house and that added weight puts stress on the roof decking which is especially worrisome in our climate that gets heavy rain and snowfall.

Why not to add a second lkayer on a roof.

Flashing around roof penetrations and sidewalls can be compromised. The savings you re going to see may be in the range of a modest 25. That second layer of shingles won t last as long. Also two layers of shingles are going to attract a lot more heat than just one layer which can lead to the shingles prematurely deteriorating.

You need to tear off the roof and install a new one. Add a layer of shingles over the newly repaired area before you install your second layer of shingles. For instance instead of just one roof on your home you now basically have two. Doing a second layer right means a lot of prep work goes into the overlay anyway and flashing which remember is the most vulnerable point on your roof is harder to guarantee.

However this is a particularly short sighted approach once you realize that layering roofing can often void the warranty. That helps your final layer of shingles look flat with a proper installation. Install a course along the snapped line then install succeeding courses using a guide or a snapped line. That s a lot of extra weight putting added stress on the roof decking.

There are already two layers of shingles on your roof most building codes only allow two layers of any type of roofing on your home. This is mostly due to the fact that a brand new roof traps much less heat than a roof with multiple layers. 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. Manufacturers believe that layering the roofing diminishes the overall performance of the roof.

This will force you to replace your roof earlier than expected. Adds value a brand new tear off roof can add to your home s resale value and is a major selling point. The second layer is also more difficult to install properly compared to new shingles. So if there are already two layers the choice is made for you.

This step is important because it brings the underlying surface back to a level height consistent with the rest of the roof plane. That in itself eats away at the savings. Most people want to add another layer to their existing roof to save money.