Roof On Top Of Another Roof

This was a first.

Roof on top of another roof.

A common house roof pitch is 5 by 12 which means it slopes up from the wall at 5 inches per foot. Unfortunately the money you save by avoiding a full roof replacement comes out of the value of your house. Place the top of each starter shingle firmly against the bottom of the shingle immediately above it and even with the eaves then nail it into place. Make sure the pitch of the trusses is the pitch that you want for your new roof.

Shingles that are raised or misshapen make it hard to lay a smooth flat layer of new shingles on top. Was inspecting a home on the old navy base in orlando and when accessing the attic they had placed a new roof trusses and all on top of the old roof. Let me get this straight your saying they built an entire new roof on top of the original one already in place. If your existing roof is fairly old there s a good chance the shingles are damaged.

More difficult to check deck when you tear off the old roof you get a look at what s underneath. Chances are your roof structure was designed for a dead load of one layer of shingles plus extra for snow and a safety margin. Use 1 5 or 1 75 inch roofing nails. The installation of metal roofing is often easier and faster than other roof types and because of its simple design and generally large size can actually be installed directly on top of existing roofing materials like asphalt shingles and foam roofing.

But because of the amount of prep work involved in overlaying a roof properly any savings are usually modest maybe 25 percent compared to a new roof. I was floored when i saw the old shingles. Installing new roof shingles over old effectively doubles the weight of the roofing so you have to make sure your roof structure can handle the extra load. The shingles likely won t last as long so the job could actually end up costing you more in the long run.

Your house will probably be worth less. If there are any pros to overlaying a roof it s saving a little bit of money. Since it s being put on top of another less than perfect roof it s likely that it may not look as good as a brand new roof would. Assuming your old roof is in good shape the additional layer can serve as added protection in case a top shingle gets blown off in a storm.