When building an exterior load bearing wall 12' high, using 2x6's, is there horizontal blocking/bracing required between the studs? If so, what are the requirements for that? ie. how many per cavity, do they stand on end or go flat, etc? IRC 2012.
If I remember right, any stud section that is over 10' tall needs blocking. Any place I have seen, has been in the center of the height, placed flat so it completely blocks the cavity. It is for fire stopping I believe, perhaps structural as well.
Besides the blocking it is often a worthwhile idea to add triangular bracing to external walls to keep them strong and straight. In the past this was often done by notching in a 1x4 into the face of the studs from the outside. These days there are much easier to install metal strappings you can install on the outside surface of the studs in an X cross formation. (The X cross format is important for strapping because it works well in length stretch resistance but not so well in length shrink (compressive).
This can have particular value in certain cases as follows:
- Local building code may require this as practice.
- Extra tall and wide walls may be built.
- The building is being constructed in an area where high winds are possible.
- The building is in a tornado zone.
- The building is in an earthquake zone.
Fire blocking is required in 1) horizontal and vertical framing spaces, like stud spaces and furred spaces at 10’, 2) intersection of walls and floors, 3) intersection of walls and attics, 4) top and bottom of stairs, and 5) at cornices. (See R302.11.)
You can use: 1) 2x solid wood, 2) 2 layers of 1x solid wood, 3) 23/32” (3/4”) plywood with joints backed up with 23/32” plywood, 4) 3/4” particleboard with joints backed up with 3/4” particleboard, 5) 1/2” gypsum board, 6) 1/4” cement based board, 7) batts or blankets of rock wool or fiberglass insulation secured in place in approved manner, and 8) cellulose insulation when installed in an approved manner. (See R302.11.1.)
Often times with the OK from the building inspector I've been able to avoid all together, the time-consuming task of installing fire blocking, on an outside wall which is insulated, which can also act as a draft stop.