Your shakes should be installed at a 7 1/2 inch exposure. Your felt should be the same & actually lay on the tips of the shakes by 3" with the next shake laying over it.
You will see the felt between the spaces & that will be your next 7 1/2" exposure line.
DC Roofing inc
I want to use hand split cedar shakes on spaced sheeting to roof an open porch. I'd rather not use felt just for aesthetic reasons (I don't want to look up and see the felt paper). Am I asking for trouble?
Cedar shakes were always installed without felt (1970's thing)
The installation process is different
The shakes need to be triple layered & the offsets between the spaces need to be 3 rows instead of 2 up.
A 24" shake will have a 7 1/2" exposure instead of 10" You will actually require about 33% more material for this installation not the 25% trhat it looks like. The reason is your making up on third of 7 1/2" not 25% of 10"
An 18" shake will have a 5 1/2" exposure instead of 7 1/2" requiring 40% more material
I built an open deck & installed 1 x 4 T & G cedar over the entire deck then strapped it with 1 x 4 hemlock & felted it as usuall. In this application it looks good underneath, has felt installed, takes less cedar & still breathes
DC Roofing Inc
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