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M Kelekci
07-05-2007, 07:23 AM
I got 2 questions.

1.Can 1x10 be used as collar tie? I am used to seeing 2X? s.

2. I know APA recommends 1/8’’ gap between roof sheating material. The house I inspected had ½’’ gap between OSBs. Is this OK or they used wrong size clips?

Sorry no photos.

Thanks in advance.

Richard Stanley
07-05-2007, 07:54 AM
1. OK
2. I assume from your question that clips were used - probably ok. I guess it is possible that ghosting of the space could show up on the roof exterior over time. The clips, properly installed, provide a minimum spacing - don't know what the max is. 1/8 - 1/2 = 3/8 difference.

Kenton Shepard
07-09-2007, 06:09 PM
2. Clips provide strength, since the edges of the panels support each other where they're clipped together. With 1/2" gap, panels will lose this support and clips will be a waste of time.
I dont see them acting as spacers. They seem to provide spaces, but the clips are solid and sheathing butts the clips, so there's no space for sheathing to expand into except between clips, which are installed every 24".

Jim Luttrall
07-09-2007, 06:39 PM
1x are fine for collar ties, the load impose will be trying to stretch the board, not bear on it.

1/2 inch is way too much space between osb sheathing or decking. I can't grasp any properly installed clip creating a 1/2 inch gap.

Richard Rushing
07-09-2007, 06:53 PM
Hello Kenton,

Actually, the primary function of an H-clip is to provide spacing (not edge support) for the decking. The spacing is designed to allow for expansion and contraction during seasonal changes.

Now, do they provide some edge support? Sure. But that is not their primary function or design (to provide strength)... it to prevent edge buckling.

Ever seen horizontal buckling or raised sections of the roof covering... not usually. Usually it will be in the form or vertical (from drip to ridge) buckling. That's because the yahoos will sometimes butt the edges up against each other.

Rich

Rich

Kenton Shepard
07-09-2007, 06:57 PM
Hello Kenton,

Actually, the primary function of an H-clip is to provide spacing (not edge support) for the decking. The spacing is designed to allow for expansion and contraction during seasonal changes.

Rich

So Rich,
Since sheathing panels are basically touching each other every 24" (at each clip) why is this effective? If spacing is the main function, it seems to me the best method is to tack a couple of 8d nail into the rafters as spaces before placing the next panel.

Jim Luttrall
07-09-2007, 08:14 PM
Actually, using an 8d nail for spacing is an old accepted practice for spacing, but then you don't get the slight increase in strength and edge alignment that the clips provide.
Jim

Kenton Shepard
07-09-2007, 08:28 PM
True, also I've never seen a problem with slamming them tight unless they get WET! I don't think temperature changes are enough to be a problem.

Richard Rushing
07-09-2007, 10:03 PM
Slamming them together *IS* the problem. If you do that then you will get what I described above... the vertical ripples on the roof covering after awhile-- moisture is unforgiving with out spacing.

As Jim stated, the 8d spacing method has been used for ever...

Rich

Michael Thomas
07-10-2007, 05:32 AM
Teco on "H" clips:

http://www.tecotested.com/documents/20061003_TTip_HClips.pdf

http://www.tecotested.com/pdfs/FAQs/EdgeClips.pdf

and panel buckling:

http://www.tecotested.com/documents/060907_TTip_BPRepair.pdf

Brandon Chew
07-10-2007, 07:45 AM
Hello Kenton,

Actually, the primary function of an H-clip is to provide spacing (not edge support) for the decking. The spacing is designed to allow for expansion and contraction during seasonal changes.

Now, do they provide some edge support? Sure. But that is not their primary function or design (to provide strength)... it to prevent edge buckling.

Ever seen horizontal buckling or raised sections of the roof covering... not usually. Usually it will be in the form or vertical (from drip to ridge) buckling. That's because the yahoos will sometimes butt the edges up against each other.

Rich

Rich

The primary purpose of the H clips is to provide edge support of the panels and to stiffen the roof deck. If you use H clips (or wood blocking), then for a given panel thickness you can increase the spacing between rafters. Or for a given rafter spacing, you can use thinner sheathing. This is backed-up by the TECO references that were provided and in the building codes (IRC).

A secondary purpose of the clips is that they designed them so that they would also provide the 1/8 inch spacing (making the "nail in the rafter" technique unnecessary). The spacing is needed to protect the installed plywood from buckling if it gets wet during construction and before the roof covering is applied (or if the roof covering subsequently leaks), more-so than to account for seasonal changes (this is true for my climate -- it could be different for a hot/humid climate in the south).

Manufacturers instructions for the H clips recommend a maximum gap of 1/4 inches between panels.

M Kelekci
07-10-2007, 08:40 AM
Thank you all.