Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Building & Construction

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 12-12-2011, 08:31 PM   #1
Member
 
Join Date: Oct 2011
Location: Phoenix, AZ
Posts: 112
Share |
Default

Shear Walls and OSB?


I'm building a 300 square foot addition with permits, etc. It comes off the side of my existing concrete block house. The addition is 2x6 framing and is tied into the concrete with anchor bolts.

I plan to use 1/2" OSB to sheath the walls, and the OSB will be providing the shear strength. Can I use regular APA Rated OSB, or do I need to use APA "Structural" OSB?

Thanks.

JeepNick is offline   Reply With Quote
Old 12-12-2011, 08:46 PM   #2
Member
 
Join Date: Dec 2008
Location: Fairbanks, AK
Posts: 1,847
Default

Shear Walls and OSB?


Jeep: No idea on which to use (I bet 99.9% of the houses built use whatever Ho De Po has on hand, though). That said, if you will be living in the space, or if there is any chance of the walls getting wet, OSB is really not as good as plywood. OSB off-gasses gunk, and swells and gets mushy when it gets wet. Just my 2 cents. I will never use OSB in a residence.

jklingel is offline   Reply With Quote
Old 12-12-2011, 08:47 PM   #3
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Default

Shear Walls and OSB?


What grade is listed on your plans that were permitted?

http://www.apawood.org/pablog/index.cfm?mode=search

Blocking for shear; http://www.apawood.org/pablog/index....al-or-Vertical

Keep it dry and gap it; http://alcor.concordia.ca/~raojw/crd/essay/essay000005.html

A different gap; http://www.buildingscience.com/docum...d%20in%20walls

Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
The Following User Says Thank You to Gary in WA For This Useful Post:
woodworkbykirk (12-12-2011)
Old 12-12-2011, 08:54 PM   #4
journeyman carpenter
 
woodworkbykirk's Avatar
 
Join Date: Sep 2011
Location: nova scotia canada
Posts: 2,654
Default

Shear Walls and OSB?


gary is right, if the wall has to have a shear rating then there has to be a spec'd sheathing to use other wise it wont pass inspection
woodworkbykirk is offline   Reply With Quote
Old 12-12-2011, 10:43 PM   #5
Member
 
Join Date: Oct 2011
Location: Phoenix, AZ
Posts: 112
Default

Shear Walls and OSB?


I drafted the plans using my neighbors recent addition plans as a guide for local requirements. My plans, nor his plans make mention of "structural grade" OSB. I purchased sheets of "Rated" OSB from my local lumber yard. I haven't nailed any up yet.

It was only after the purchase that I realized there was actually another grade higher of OSB rated "Structural" which from what I can find is used when there are extreme shear forces at play, such as in areas with high seismic activity. I found a listing of seismic design categories from A to F, A being little/no seismic stress and progressing from there. My area is listed as category B by the building department which is only moderate.

I'd like to avoid having to buy more sheathing, but only if what I have is the right material for the job. It has to pass inspection, and then it has to stand up to time. I don't ever want to have to tear it out and replace it. My understanding is that OSB has come a long long way from where it used to be. The glues have improved dramatically and with better glue comes better shear strength and better water resistance. The panels I purchased actually have a stamp on them that they are resistant to water.
JeepNick is offline   Reply With Quote
Old 12-13-2011, 08:16 PM   #6
journeyman carpenter
 
woodworkbykirk's Avatar
 
Join Date: Sep 2011
Location: nova scotia canada
Posts: 2,654
Default

Shear Walls and OSB?


this sounds like it could be a can of worms
woodworkbykirk is offline   Reply With Quote
Old 12-13-2011, 10:16 PM   #7
Registered User
 
Join Date: Mar 2009
Posts: 9,968
Default

Shear Walls and OSB?


The person to ask is your local AHJ. The Inspector will be checking if it meets code or not, call him. There are many grades/species of OSB and applications. Some are even designed for the strength-axis running 4' rather than normal 8', go figure.
Most are water resistant due to the wax used in the press to release them. The later ones are also treated at the edges against water intake resulting in edge swell. I could really get in to why not to use OSB, though I doubt you want to hear that now....

Take lots of pictures for the Inspector and your H.O. Insurance to show it was built to minimum Code and permitted.

Gary

__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.