single row of brick for foundation wall

Usually, the width of the sill plate is the same as the width of the masonry foundation. A ten-inch wall would call for a ten-inch sill plate, preferably anchored into the block back-up with bolts or approved straps. Then the wall can bear on the outside four inches if 2x4 studs are permitted. Usually, though, the wall bears on floor joists, which bear on the plate. That’s the practice that’s typical here in the northeast. Seems to me it would be good practice anywhere.

The bricks are probably stronger than the block, so I wouldn’t worry about compressive strength. The question in the pictured example is how well the bricks are tied to the block, and at this point, there is no way to tell.

“2006 IRC R404.3 Wood sill plates. Wood sill plates shall be a minimum
of 2-inch by 4-inch
(51 mm by 102 mm) nominal lumber. Sill
plate anchorage shall be in accordance with Sections R403.1.6
and R602.11.”


2x4 are not allowed (interpretation of code officials in several counties I built in) on a pier and curtain because…

  1. Pier and curtain walls require that the bandboard (also called header joists) be doubled.
  2. All Joists that tie into bandboards must have 1 1/2 inch bearing.
  3. Double bandboards are 3 inches thick which means the joists are only bearing on 1/2 inch of sill plate.
  4. You must now put a ledger strip on or you must use approved hangers.

While not all savy building inspectors catch that part of the code, I always tended to find the ones that did. :frowning:

In Lincoln County I used a 2x6 sill on a crawl and that was turned town…he showed me the code (don’t remember it now) but basically it had to do with the way the sill plate was not tied to the bandboard, and therefore could not count as a ledger.
My only saving grace was that he got out to the site early just as we had finished the installing the sill plates… I had to exchange them for 2x8…still couldn’t figure that one out…but then again this guy was a arse. On several occassions I had to get an engineering letter to prove that his interpretation was wrong on some of the things we did (stick framing of the roof system). My engineer agreed with him on the 2x4 sill plate issue.



Interesting. Thanks Jeff.