H clips

[David C. Macy]

Home was a new built in 2005/2006.

Home had rafter framing with OSB.

Question. No H clips. I spoke to builder & he stated that they are not required. He did say that in truss framing they are a good practice to install.

Is what he is staing true about the H clips?

[Harold E. Miller]

David
From the picture it appears that the rafters ar approx. 12" OC ? maybe 16" OC at the most... at these limited spans I don't see where H clips would help alot. In this case I don't see a problem.
If it were 24" spans it would be a different story.
The IRC does not refer to H clips under sheathing requirements.

[David C. Macy]

Sometimes it is hard to remenber what is required & what isnt.

You guys on this board are a great help & I appreciate your knowledge & professionalism.

[bsumpter]

I didnt see anything in Code Check....

[Frank M. Carrio, CMI]

Originally Posted by dmacy

Home was a new built in 2005/2006.

Home had rafter framing with OSB.

Question. No H clips. I spoke to builder & he stated that they are not required. He did say that in truss framing they are a good practice to install.

Is what he is staing true about the H clips?

I hope that this is of some help.
Here is what is listed in the IRC International Residential Code {ICC}

TABLE R503.2.1.1(1)

ALLOWABLE SPANS AND LOADS FOR WOOD STRUCTURAL PANELS FOR ROOF AND SUBFLOOR SHEATHING
AND COMBINATION SUBFLOOR UNDERLAYMENT a, b, c

For SI: 1 inch = 25.4 mm, 1 pound per square foot = 0.0479 kN/m2.
a. The allowable total loads were determined using a dead load of 10 psf. If the dead load exceeds 10 psf, then the live load shall be reduced accordingly.
b. Panels continuous over two or more spans with long dimension perpendicular to supports. Spans shall be limited to values shown because of possible effect of concentrated loads.
c. Applies to panels 24 inches or wider.

d. Lumberblocking, panel edge clips (one midway between each support, except two equally spaced between supports when span is 48 inches), tongue-and-groove panel edges, or other approved type of edge support.

e. Includes Structural 1 panels in these grades.
f. Uniform load deflection limitation: 1/180 of span under live load plus dead load, 1/240 of span under live load only.
g. Maximum span 24 inches for 15/32- and 1/2-inch panels.
h. Maximum span 24 inches where 3/4-inch wood finish flooring is installed at right angles to joists.
i. Maximum span 24 inches where 1.5 inches of lightweight concrete or approved cellular concrete is placed over the subfloor.
j. Unsupported edges shall have tongue-and-groove joints or shall be supported with blocking unless minimum nominal 1/4-inch thick underlayment with end and edge joints offset at least 2 inchesor1.5 inches of lightweight concrete or approved cellular concrete is placed over the subfloor, or 3/4-inch woodfinish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf.
k. Unsupported edges shall have tongue-and-groove joints or shall be supported by blocking unless nominal 1/4-inch-thick underlayment with end and edge joints offset at least 2 inches or 3/4-inch wood finish flooring is installed at right angles to the supports. Allowable uniform live load at maximum span, based on deflection of 1/360 of span, is 100 psf, except panels with a span rating of 48 on center are limited to 65 psf total uniform load at maximum span.

[Marcel R. Cyr]

David, a little more information I found.

http://www.tecotested.com/AllTechnicalInformation.htm

http://www.tecotested.com/AllTechnicalInformation.htm

http://www.umass.edu/bmatwt/publicat...s_plywood.html

Hope this helps.

Marcel

[gbrasseur]

Where can you find IRC online?

[Carl A. Brown]

But by putting in the h clips on it makes the 1/8 inch spaceing the mfgr. calls for around the sheets. For proper installation of the OSB!

[Marcel R. Cyr]

That's right Carl.

Do you think that most Contractors would loggically figure that out?

No brainer to us, but you could not believe how hard it is to pound in that information to some of these people sometimes.

Marcel

[homebild]

You can find some free model ICC codes here:

http://www.ecodes.biz/index.cfm?vals=Free_State

Bear in mind that these are state or jurisdiction specific (although they retain most of the overall code) and not all jurisidictions use the same year model code.

There are also state modification to the adopted ICC codes.

Check your particular state's website for code adoption modifications.

You can find Pennsylvania's here:

http://www.dli.state.pa.us/landi/cwp...a=310&q=210892

[Robert J. OConnor]

H-Clips are not always required.

H-Clips or blocking are only required for edge support with thinner panels and/or larger rafter spacing where the panel may sag between rafters/chords without that.

They are also helpful, but not a requirement, to assist with achieving the recommended 1/8" gap between adjacent panels.

Here are a few articles/tables I had handy (the second one has a sample table to go with the notes Frank posted above ... note the allowable span difference with and without "edge support"). Hope they help.

JMO & 2-nickels ...

[Carl A. Brown]

They need to make it code and even on the walls just to make sure the 1/8 inch gap is there! After all the sheets are sized for the spaceing. Then when the houses are built it would be easy for the codes officials to see the spaceing even if there is a housewrap on the structure!

[Frank M. Carrio, CMI]

Originally Posted by roconnor

H-Clips are not always required.

H-Clips or blocking are only required for edge support with thinner panels and/or larger rafter spacing where the panel may sag between rafters/chords without that.

They are also helpful, but not a requirement, to assist with achieving the recommended 1/8" gap between adjacent panels.

Here are a few articles/tables I had handy (the second one has a sample table to go with the notes Frank posted above ... note the allowable span difference with and without "edge support"). Hope they help.

JMO & 2-nickels ...

Hi Robert,

I tried to attach the table listed in the IRC and failed to do so. You have provided some valuable information to our fellow NACHI members.

Kudos!

[Frank M. Carrio, CMI]

Hi Dave!

I though that I would let you know that the ICC codes are in effect for all of Ohio.

Ohio Statewide

• 2003 International Building Code
• 2003 International Energy Conservation Code
• 2003 International Existing Building Code
• 2003 International Fire Code
• 2003 International Fuel Gas Code
• 2003 International Mechanical Code
• 2003 International Plumbing Code
• 2003 International Residential Code

[Kenton H. Shepard, CMI]

Originally Posted by dmacy

Home was a new built in 2005/2006.

Home had rafter framing with OSB.

Question. No H clips. I spoke to builder & he stated that they are not required. He did say that in truss framing they are a good practice to install.

Is what he is staing true about the H clips?

It's an engineering call. Many, many homes have been built without them. They're a good idea with framing on 24" centers, but you can't call it a defect unless you're looking at a set of plans that call for them and you see them missing. It's not a code inspection.

I never call them if they're missing. I call excessive deflection if I find it, a problem which is sometimes helped by H-clips.