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JIM MURPHY
03-21-2013, 07:03 PM
What is the requirement for using clips on a 1/2 " roof deck 24 " span dated to 1985. There was none at this house.

Jim
Harry Janssen
03-21-2013, 07:09 PM
half inch ply does not require clips at 2 feet OC,but 3/8 ply does at 24 OC.
CHARLIE VAN FLEET
03-21-2013, 07:59 PM
are you talking about h clips on roof sheathing?

cvf
Bruce Conway
03-22-2013, 06:44 AM
What is the requirement for using clips on a 1/2 " roof deck 24 " span dated to 1985. There was none at this house.

JimAs a former contractor, I've done many roofs and never used 1/2" or 3/8/" plywood on 24"centers. I believe code requires 5/8" minimum 24oc. However, I think it's a good practice to use clips with 5/8" decking on 24oc. 1/2"plywood at 16oc is still weak and if you are a 200lb man standing on a joint where the plywood meets, it will give. You may not like the H clips but they are a little bit of insurance.
Phillip Norman
03-22-2013, 08:35 AM
As a former contractor, I've done many roofs and never used 1/2" or 3/8/" plywood on 24"centers. I believe code requires 5/8" minimum 24oc. However, I think it's a good practice to use clips with 5/8" decking on 24oc. 1/2"plywood at 16oc is still weak and if you are a 200lb man standing on a joint where the plywood meets, it will give. You may not like the H clips but they are a little bit of insurance.
I see lots of attics as a weatherization contractor, where I do all the work. I see only 15/32" plywood sheathing, where I am able to check. Here is a relevant observation in a blog post (http://energyconservationhowto.blogspot.com/2009/08/using-baffles-with-attic-batt.html).
John Kogel
03-22-2013, 01:25 PM
H-clips - patent granted (to Mr Simpson) in '86, with patents for an earlier 3-legged version in '82.

H clip - M&O Products, Inc. (http://www.freepatentsonline.com/7444792.html)

Likely not required in the mid-80's in your area. I would not call it a defect under the circumstances, but I might report the 1/2" plywood on 24" centers as a weakness and move on. First confirming that it really is 1/2" of course.

BTW, H-clips have a second purpose. They provide a gap between the sheets to allow for swelling.
Barry Larence
03-24-2013, 12:36 PM
Not Required in Calgary on 1/2" plywood or OSB @24" o/c, but anything less must have