From the 2006 IRC. (underlining is
mine)
- SECTION R319
- - PROTECTION AGAINST
DECAY
- - - R319.1 Location required.
Protection from decay shall be provided in the following locations
by the use of naturally durable wood or wood that is preservative treated in
accordance with AWPA U1 for the species, product, preservative and end use.
Preservatives shall be listed in Section 4 of AWPA U1.
- - - - 1. Wood
joists or the bottom of a wood structural floor when closer than 18 inches (457
mm) or wood girders when closer than 12 inches (305 mm) to the exposed
ground in crawl spaces or unexcavated area located within the periphery of the
building foundation.
- - - - 2. All wood framing members that rest on
concrete or masonry exterior foundation walls and are less than 8 inches
(203 mm) from the exposed ground.
- - - - 3. Sills and sleepers on a
concrete or masonry slab that is in direct contact with the ground unless
separated from such slab by an impervious moisture barrier.
- - - - 4. The
ends of wood girders entering exterior masonry or concrete walls having
clearances of less than 0.5 inch (12.7 mm) on tops, sides and ends.
- - -
- 5. Wood siding, sheathing and wall framing on the exterior of a building
having a clearance of less than 6 inches (152 mm) from the ground.
- - - - 6.
Wood structural members supporting moisture-permeable floors or roofs that are
exposed to the weather, such as concrete or masonry slabs, unless separated from
such floors or roofs by an impervious moisture barrier.
- - - - 7. Wood
furring strips or other wood framing members attached directly to the interior
of exterior masonry walls or concrete walls below grade except where an approved
vapor retarder is applied between the wall and the furring strips or framing
members