Unbuckling Your Walls

Pop Quiz:

Why does wall sheathing buckle?

If you answered something like studs at 24" o.c., I'm sorry to disappoint you.  The most common cause of wall sheathing buckling is because it wasn't properly gapped.  We've hounded on this before.  But now the APA has developed a mobile tool that will help educate builders on some of the most common building issues.

See this and many more tips at the APA website.  Tambien en español!

• Prevent Buckling with Proper Spacing includes spacing recommendations for APA Rated Sheathing, APA Rated Sturd-I-Floor®, and APA 303 Siding. (Form M300, now available in Spanish)
• Construct a Solid, Squeak-Free Floor System describes how to prevent floor complaints and callbacks with proper floor sheathing installation. (Form Q300, now available in Spanish)
• Minimize Nail Pops describes how to reduce nail pops through recommended fastener selection and installation. (Form S300, now available in Spanish)
• Storage and Handling of APA Trademarked Panels provides guidelines to help protect panels from damage in storage, during shipment, and on the job site. (Form U450)
• APA Panels for Soffit Applications provides information on recommended panels and spans for open and closed soffits. (Form N330)
• Finishing APA Rated Siding describes recommended finishes and application recommendations for APA Rated Siding. (Form Q350)
• Proper Storage and Handling of Glulam Beams provides recommendations for storage and handling of glulam beams. (Form R540)
• Minimize Glulam Checking Through Proper Storage and Handling provides tips for preventing glulam checking. (Form F455)
• Proper Installation of APA Rated Sheathing for Roof Applications provides step-by-step instructions for roof sheathing installation. (Form N335)
• Proper Selection and Installation of APA Plywood Underlayment includes information on selection, handling, installation and fastening APA Underlayment panels. (Form R340)

Lumber Sizes

Ever notice that a 2x4 isn't really 2"x4"?  What's with that?   Fact is that the piece of wood started at 2"x4" but is called "rough sawn", that is it has unfinished faces.  The stick is then sent through a planer to smooth the faces and reduce serious splinter casualties.  About 1/4" is shaved off of each of the four faces resulting in a lesser dimension than you would expect.  Besides, who would want to say "one-and-a-half by three-and-a-half"?  Mind the twist at 2x8 and beyond...

Now pay attention as we mention dimension convention:

1x:

• 1x2 = .75" x 1.5"
• 1x3 = .75" x 2.5"
• 1x4 = .75" x 3.5"
• 1x6 = .75" x 5.5"
• 1x8 = .75" x 7.5"
• 1x10 = .75" x 9.5"
• 1x12 = .75" x 11.5"

(5/4 material is similar but is 1" thick)

2x:

• 2x2 = 1.5" x 1.5"
• 2x3 = 1.5" x 2.5"
• 2x4 = 1.5" x 3.5"
• 2x6 = 1.5" x 5.5"
• 2x8 = 1.5" x 7.25"
• 2x10 = 1.5" x 9.25"
• 2x12 = 1.5" x 11.25"
• 2x14 = 1.5" x 13.25" 

3x: (for those odd structural plates that engineers like to call out)

• 3x4 = 2.5" x 3.5"
• 3x6 = 2.5" x 5.5"

4x:

• 4x4 = 3.5" x 3.5"
• 4x6 = 3.5" x 5.5"
• 4x8 = 3.5" x 7.25"
• 4x10 = 3.5" x 9.25"
• 4x12 = 3.5" x 11.25"
• 4x14 = 3.5" x 13.25"

6x and beyond follows typical pattern as above.

And while we're at it, how about some typical engineered wood sizes.

I-joists are created by standing a piece of OSB or plywood upright and capping it with a 2x flange.  The result looks like a capital serif 'I' hence the name.

I-joist flange widths (varies by manufacturer):

• 1-3/4"
• 2"
• 2-5/16"
• 3-1/2"

I-joist heights (total height):

• 9-1/2"
• 11-7/8"
• 14"
• 16"
• 18"
• 20"
• 22"
• 24"

Laminated Veneer Lumber (LVL) beams are created by gluing several sheets of 7/8" thick plywood together.  Installation is by standing them on edge so that the profile looks similar to |||

LVL widths:

• 1-3/4" (2 layers)
• 2-5/8" (3 layers)
• 3-1/2" (4 layers)
• 5-1/4" (6 layers)
• 7" (8 layers)

LVL heights:

• Any height possible though generally intended to match I-joist material.  Can match dimensional as well.

Glu-lam beams are created by gluing and compressing several layers of post milled dimensional lumber together.  The whole beam is then planed again to create an even surface.  For this reason, glu-lam beams are slightly narrower than dimensional lumber.  *The industry has recently changed to also offer Gle-lams in full 5-1/2" widths as well.  Heights are always in multiples of 1-1/2" due to the size of the plies.  *The industry has recently changed to offer heights that are consistent with solid sawn and engineered lumber as well.  Due to general engineering practice the height should always exceed the width though rare exceptions always exist.

Glu-lam widths:

• 3-1/8"
• 3-1/2"
• 5-1/8"
• 5-1/2"
• 6-3/4"
• 7-1/4"
• 8-3/4"
• 9-1/4"
• 10-3/4"

Glu-lam heights:

• 6"
• 7.5"
• 9"
• 9.5"
• 10.5"
• 11.875"
• 12"
• 13.5"
• 14"
• 15"
• 16.5"
• 18"
• 19.5"
• 21"
• 22.5"
• 24"

Glu-lams can be used as posts as well.  A 3-1/8"x6" glu-lam post is sturdier than a 4"x6".