Cedar Shakes

[Mike Tracy]

I looked at a house this morning that has two layers of roofing. The visible layer is a cedar shake roof and the layer under the cedar is an asphalt shingle. I have never seen this type of application and I am curious as to whether or not it is a proper install.

My gut feeling is no but can't seem to find anything on it. i am trying to complete the report and need to make a decision soon.

Thanks for your help.
:confused:

[Raymond Wand]

Someone was trying to save money by not stripping the asphalt shingles off and paying for disposal fee.

The wood shingles/shakes will have their life shortened due to being applied on a solid backing. Just as wood shingle life is shortened by placement on plywood sheathing as opposed to space plank which allows the shingles to dry.

In my opinion its not the best way to install an expensive product like wood shingles.

[Eric Barker]

Nothing wrong with writing non-professional / unorthodox installation. That being the case there's nothing wrong with recommending a qualified roofer review and correct as necessary. Let someone else put their neck in the noose if they want to say it's ok.

[John Kogel]

Cedar shingles or shakes nailed flat to any solid surface is wrong, what Raymond said. If they laid open strapping on top of the asphalt shingles, then the roof will last longer, so not as bad.

BTW, be sure they are actually split cedar to call them shakes. I've mistaken badly weathered shingles for shakes until I got up close to them. Shingles of course have a shorter lifespan because of the sawn surface.

[Mike Tracy]

Thanks for the help. I advised that the installation was uncommon and that they should have a licensed roofing contractor examine the installation.