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Blocking in exterior wall

cwright7080

Registered User
Joined
Mar 8, 2018
Messages
3
Location
mechanicsville,va
Hi guys,
I have been unable to locate any information in the VRC book on how blocking
in walls should be spaced, plenty on floors, but none on wall construction. Am I
over looking it or is it not stated? I have a 15' high wall ( to apex of gable ) and
wanted to make sure I put the right spacing of blocking, so I don't fail any
inspections.
 
Hi guys,
I have been unable to locate any information in the VRC book on how blocking
in walls should be spaced, plenty on floors, but none on wall construction. Am I
over looking it or is it not stated? I have a 15' high wall ( to apex of gable ) and
wanted to make sure I put the right spacing of blocking, so I don't fail any
inspections.

Check out R302.11 fireblocking:

2013 CRC said:
R302.11 Fireblocking. In combustible construction, fireblocking
shall be provided to cut off all concealed draft openings
(both vertical and horizontal) and to fonn an effective
fire barrier between stories and between a top story and the
roof space.
Fireblocking shall be provided in wood-frame construction
in the following locations:
1. In concealed spaces of stud walls and partitions, including
furred spaces and parallel rows of studs or staggered
studs, as follows:
1.1. Vertically at the ceiling and floor levels.
1.2. Horizontally at intervals not 10 feet
(3048 mm).
2. At all interconnections between concealed vertical and
horizontal spaces such as occur at soffits, drop ceilings
and cove ceilings.
3. In concealed spaces between stair stringers at the top
and bottom of the nm. Enclosed spaces under stairs
shall comply with Section R302.7.
4. At openings around vents, pipes, ducts, cables and
wires at ceiling and floor level, with an approved material
to resist the free passage of flame and products of
combustion. The material filling this annular space
shall not be required to meet the ASTM E 136 requirements.
5. For the fireblocking of chimneys and fireplaces, see
Section RI003.19.
6. Fireblocking of cornices of a two-family dwelling is
required at the line of dwelling unit separation.

Interestingly when I started out it was over 7', then it went to 8' eliminating it in most 8' ceiling homes but bringing up the lateral support issue with line-wire stucco applications so they required centerline blocking at mid-span for the first 4' off each corner for line-wire applications, then sheathing came back eliminating the lateral support requirement, then it went to 10' as above.

BTW, the above quote is the 2013 CRC, but if you are not in Calfiornia there are no vertical margin lines indicating any changes from the 2012 IRC.
 
If you are referring to blocking used as lateral restraint, then 2012 IRC table 602.3(5).
2012 IRC.JPG
Buckling.JPG

cwright7080,
The first time I read your post I was a little confused; the abbreviation VRC is Part II of the Virginia Uniform Statewide Building Code, also known as the “Virginia Rehabilitation Code,” (or the “VRC”)

For this site I would use IRC.
 
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