Originally Posted By: tutley This post was automatically imported from our archived forum.
Concerning unsupported edges (horizontal edges) of plywood or OSB roof sheathing panels: I do not see H - clips on the newer homes, only on the older homes. Is this worth flagging on an inspection report? If it is required, can anyone tell me where it is printed?
Originally Posted By: dvalley This post was automatically imported from our archived forum.
Thomas,
H clips are not required by code. The purpose of H-clips is to reduce the effective spacing of the roof rafters and stiffen the roof deck, and they are an alternative to utilizing solid blocking.
The clips are slipped over the edges of the plywood and OSB sheathing between the rafters to keep the edge of each sheet aligned with its neighbor, which reduces the likelihood of warping. When you place the H-clip at the halfway point (12") between the rafters, the plywood stiffens. As a result the roof shingles nail easier and the roof will remain straighter over time (no sags with accumulated load). H-clips can also strengthen any horizontal seams between rows.
H clips are an option for Carpenters. Some utilize these at all seams to leave room for the sheathing to expand and contract with the change in moisture/temperature and others utilize these to replace any blocking at the edge supports.
Here is a table for the spacing requirements of supports on the underside of sheathing as you described...
Originally Posted By: tutley This post was automatically imported from our archived forum.
David,
Thanks for the info. So, apparently, H - clips are not an issue with 15/32" OSB, rated 32/16, supported 24" o.c., even though the H - clips would help maintain the 1/8" spacing that is specified on the stamp.
I did find something about this in IRC 602.10.7, but this has to do with wall bracing.
Originally Posted By: Scott Drake This post was automatically imported from our archived forum.
Are you seeing more 7/16" 24/16 panels used as roof sheathing? If so, the 24" roof span does not require edge support. If you look at the TECO Design and Application Guide, table 10, you can see that the maximum allowable span is the same for both unsupported and supported. The product is tested to the PS 1 or PS 2 standards without using a clip for this span Only. All other roof spans are tested using a clip. I would say that the a clip should be installed in the field if the span exceeds the unsupported max allowable span in table 10.
Originally Posted By: jrooff This post was automatically imported from our archived forum.
Around here with 24" oc trusses for sheathing if you do not have bracing you better have clips and if no clips your a$$ will be putting up bracing according to our inspectors and guess who has to sign that permit to continue.