Roof on top of another

This was a first. 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. Ever seen this? I was floored when I saw the old shingles.

Got any pictures?

Let me get this straight…

Your saying they built an entire new roof on top of the original one already in place? Is the original roof flat or pitched? Yes please post pictures. First for me also.

Bill lol

Old was flat


Why did they have shingles on a flat roof?

I’m at a loss here. lol To me the load of both roofs would be to much. I would possibly site a safety concern and consider a structural engineer for further evalution. But again I’m at a loss can’t wait to see what others say.


I have actually seen this quite a bit. But usually it is on an older garage or larger shed that has been “remodeled”. Never seen it on an actual home. Interesting.

It was not flat. I am sorry. Very low pitch

Not that un common Gary…increase the pitch for better appearance and performance…go over existing to save cost of removal and need for keeping water and desbris out of attic and house during construction…not too popular with fire departments though cause it sure can make a fire much harder to put out when it gets between roofs…jmo…jim

Fairly common here, especially in 4 & 6 plexes with older flat T&G roofs. They add trusses (usually 6/12 pitch)/roofing and insulation to the old flat roof at the same time.

On an insulation estimate in the mid 1980’s, found a house that started by pushing 2 smaller homes together about 1850 and adding a new roof over all. In the following 120 or so years, 2 more additions and roofs were added…in one area there were 3 roof systems. Took me 2-3 hours figuring out how and where to create a continuous air and thermal barrier in these attics.

I had one this year the same way, it was built over an existing flat roof. The seller had the approved blueprints from when the extension was done.

No comment on this or the new bathfan…:stuck_out_tongue:

John Kogel





Too much for what? Certainly not the walls… This is how far the entire side of the rafters got knocked down and cracked on an entire side.

This is a photo of a job we did last November.

1 layer of shingles on top of plywood sheathing, right?

No. Under that sheathing was a 2 layer shingle roof on top of the original decking, which was covered up by the gutter apron drip edge metal in the areas we set up the ladder to do our inspection and base our estimate on.

This was for an insurance damage claim, where a large2-3 foot diameter tree fell on the house and the detached garage.

The insurance company, Allstate, although kept informed of the additional work required that was hidded, is not allowing the extra charges to be paid to the home owners, who were counting on full replacement cost coverage, minus their deductible.

I even created a forum, just to be able to keep the adjuster informed of every photo of job progress on a daily basis and he agreed verbally that the additional work needed to be done.

If you want to see about 200 more photos, follow this link:


From an inspection standpoint, I guess there are a few ways to handle this, maybe suggesting further inv. by specialized contractor etc…

For discussion:

Without seeing the pictures, my concern would be


Attachment. did someone simply cut back existing tails and nail something down? ie. was there material (shingles, paper) between framing members new and existing.

Types of trusses - a lil out of SOP, but trusses are supposed to bear at specific points ie. 2 & 3 point trusses being common here. if it was a low pitch roof, i would guess they raised the lower wall by way of cripples, wall and shear/crossbrace depending on height etc.

Vapor barrier - if this install is above living space - a few concerns with type of insulation and vapor barrier come into question

Load - anymore, most jobs like this would fall into the consideration of a structural engineer as the additional weight may fall outside of the capacity of existing footings.

I haven’t seen anything just like it with existing sheating, paper and shingles still in place. Mickey Mouse more than likely imo.