Wood shake roof sheathing

Do you guys (and girls) make any comment in your reports about the potential need for new decking (and additional cost) when a re-roof is needed and the sheathing is wood shake?

Today’s 1915 house had asphalt shingles on top of wood shakes.

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Yup, they should know what the future holds.

The manufacturers listed service life of any exterior veneer, including roofing or siding, is directly related to the substrate that it is attached to.

Installing a good product upon an inferior substrate will adversely affect its service life.


your a home inspector not a roofer? report the roof conditions and move on…if its bad or needs repairs rec. roofer…staywith in the sop…just my 2 cents. Now Iam a roofing contractor and I would not add that in my report.

It looks like you’re looking at the underside of wood shingles NOT shakes. If so, you can go over them ONCE with composition shingles

Dan, the comp. shingles present were end of life. When they’re replaced, won’t the wood shingles have to come off also?

Yes under most current codes AND by most insurance companies

Thanks guys. Here’s how I said it:

“The composition shingles have been installed over an existing wood shingle roof. There is no other roof sheathing, which means that when the current layer of shingles is removed, the roof structure will likely have to be totally re-sheathed with plywood or oriented strand board (OSB), which will significantly affect the cost of re-roofing the house. We suggest that you have the roof and attic structure evaluated by a licensed roofing contractor prior to close of escrow because the cost of re-roofing could affect your budget or evaluation of the home.”

Well stated Joe, Can I steal that narrative? I usually comment on older homes with this situation, even If I see sheathing. I have personally stripped 100 year old homes and buildings that have had 2-3 layers of asphalt and 1-2 layers of shakes. Its NOT fun, and definitely not cheap.

Those things are still around ? Havent seen one in years. That is a nasty job.

Yes to anyone who wants it.

In the past 30 days, I’ve done 2 inspections for this client and both times the roof structure was the same. She is bound and determined to buy an old home. I don’t know if she’ll walk on this one or not.

I am a working GC… I have no problem speaking on those items that I am more than qualified to speak of… that is one of the reasons people hire me.

In our state SOP it clearly states that opinions based upon our training, experience and knowledge are acceptable.

I know of clients and agents that get tired of using HI’s whose reports are constantly filled with…“further evaluation warranted by a qualified…blah, blah, blah”

I know of one agent that does upper end homes that simply hires a SE, Electrician, HVAC contractor, Plumbing contractor and a GC… I can understand where she is coming from.



I rarely refer to a licensed trade for further evaluation, only for repairs/corrections to what I find. I do not quote on questions from clients about costs for major renovations or changes being considered by them if they buy.


Good article Marcel. Thanks.

Not allways…will depend on your local building dept. Could be wrong but think I read on most comps that if you install over shingles it will void the warranty…something to think about…opps qouted the wrong line…

If you put on another layer of comp shingles, then that would be 3 layers total counting the wood. Even if allowed (which I don’t think it would be), that would be incredibly stupid.

In the early 80’s the wood shingles were not counted in the layers but were equall to a layer of sheating. But then you would also see 4 or 5 layers along with 90#. That was the Chicago way.