# Rip 4'x8'x 3/4' plywood roof sheathing to 2'x8' for easier install?



## WallyPop (Jul 20, 2009)

HD offers to rip my 5/8"x4'x8' plywood purchase to either 16" or 24" widths.

This way the cut pieces are 1/2 or 1/3rd lighter than a complete sheet but still straddle (3) 2'-0" spaced rafters.  Where the cuts took place I'll just butt together again.

Butting together again will shrink (2) pieces of 24" width by the amount of one saw kerf or shrink (3) pieces of 16" width by the amount of (2) saw kerfs.  Is this of any consequence?

Also,  I plan to use roofing clips each 4' width total as if I were installing actual unripped 4x8 sheets for thermal spacing.  Should I use similar clips between the cut pieces ?  for strength?  for thermal?  or not at all?

I'm doing this alone as a challenge to see if I can, other-wise I'd hire two moonlighting roofing pros and let them install the sheathing.  The shingles I hope to haul up by breaking the bundles into quantities I can handle and installing over suitable underlayment.  Roof slope is 4/12 so I feel reasonably secure.

My fall back position is:  pro's do the the sheathing and shingling.  I'll do the remaining framing, installing vinyl siding, soffit/gable venting, etc..  It's an unheated garage so I see no need for ridge venting.

Any comments/suggestions, tips.


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## inspectorD (Jul 21, 2009)

If you install the sheets this way, it makes them weaker at the seams which do not have any support. Installing "H" clips will help. 
Another downside is appllying the shingles to a roof with seams this large. Try to space the shingles so they do not fall on a seam where you will nail them.
A 4x8 sheet makes a better diaphram structural wise, If you could get someone to do that part for you, or help do it, you end up with a better roof overall.


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## WallyPop (Jul 25, 2009)

Thank you Inspector.  When you state "seams this large" I guess you really meant "seams this many", which then increases the probability of nailing shingles in close proximity to a seam or on the seam itself.  

The same problem exists, if I understand you correctly, though less often of course, where the full 4'x8' sheets also incur a seam, especially since a 1/8" thermal expansion spacing is required.  I guess the "H" clips then serve a dual purpose as spacer AND support.

As a "stubborn old coot", I could, with some measure of difficulty and ingenuity, glue or otherwise fasten plywood strips underneath the seams and solve the nailing problem, but at great expense to my standing as a "rational old coot".

I'll hire me some young bodies.   Thanks again.


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## inspectorD (Jul 25, 2009)

Thanks for understanding my ramble... good luck with your project.:


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