Replies

1. 
   woodroe | May 17, 2007 01:22am | #1

   We always block our seams. I had an inspector call me on it 20 years ago, I've blocked them ever since. It is not something new, and doesn't give you "extra" shear strength, but the required shear strength.

1. 
   ChrisV | May 17, 2007 03:43am | #2

   Woodroe,

       Do you do the blocking before the sheathing or after and are there any quick techniques? In this case I am stuck to doing after the sheathing.

    

   Thanks,

   Chris

1. 
   SBerruezo | May 17, 2007 03:48am | #3

   Generally out here we get sheets (run vertically) to span from mudsill to top plate to tie everything together. I'm no engineer, but what I was told is that this increased the strength and eliminate the need for horizontal blocking. It made sense to me. In CA, though, our seismic stuff is different than most parts of the country. 

2. 
   dovetail97128 | May 17, 2007 07:07am | #4

   Chris,
   Either way works. If you don't have them in it isn't difficult to toe nail one end of the block to a stud then thru nail through the next stud into the block .
   Here I can put the blocks flat to the sheathing or perpendicular to match the studs depth .
   Been code here for a lot of years to block all edges of shear panels.
   "Poor is not the person who has too little, but the person who craves more."...Seneca

1. 
   ChrisV | May 17, 2007 08:15am | #5

   Dovetail,

      One other question, it has to be done on all the panels...the full length of the building? or just on the corners and short walls (i.e. walls to the sides of a garage door)?

    

   Thanks,

   Chris

1. 
   dovetail97128 | May 17, 2007 08:27am | #6

   Chris, no easy answer here. It is mandatory at the shear panels (which will include those either side of the garage door), the need for shear panels depends on your design and how often you have openings for windows, doors etc. If I recall correctly it was every corner and not more than 25' space without a shear panel. I have been away from residential for a few years so as the code changes my memory of whats needed is wrong.
   Hopefully for you someone with current code knowledge will give some input. I used to simply do it every where just because it wasn't that difficult nor did it take that long. Added benefit is that it does hold the sheathing panels flat along the horizontle seams.

   "Poor is not the person who has too little, but the person who craves more."...Seneca

2. 
   ChrisV | May 20, 2007 10:10pm | #7

   Hi All,

   Thanks for the advice.

    I did some further research in IRC 03' and found in R602.10.7 that there is an exception for horizontal blocking (not required) which applies to seismic categories and R602.10.1 method #3. Arizona is within seismic categories A,B,C and ALL of the walls were sheathed with 1/2" OSB on 16" O.C. studs.

   Oh well the blocking is done, but it was extra work not required and we did not want to get on the bad side of the inspector.

   Chris

    

3. 
   fingersandtoes | May 21, 2007 03:51am | #8

   Here in B.C. we are required to provide blocking at the mid-point of any stud wall over 10'-0". No requirements for blocking sheathing joints though. In fact we have to gap it 1" for air movement in the stud cavities.

2. 
   IdahoDon | May 21, 2007 09:12am | #9

   With IRC, if the sheathing is in the area considered a sheer wall then it requires blocking, but ajoining sheathing does not.  The entire wall does not need to be blocked.

   Having said that some durisdictions will say if a wall is covered with a structrual sheathing then the edges need to be blocked reguardless.  We've has some inspectors follow that line of reasoning while other did not.

   In the calmer seismic zones UBC does not require the blocking.

    

   Beer was created so carpenters wouldn't rule the world.