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Frank Bombardiere
09-27-2009, 04:21 PM
I don't know of any requirement for a garage to be framed with treated wood other than the sill plate. I have a friend that has a complaint from someone that has a contractor buddy that was doing some remodeling on their garage claiming that the garage should have been framed with treated wood. I have not ever heard of it. At least not around here. Have any of you heard of such a thing?

Frank Bombardiere
09-27-2009, 05:38 PM
Nevermind, I just found out that he was talking about the sill plate only, which should be treated lumber.

Jerry Peck
09-27-2009, 08:27 PM
I don't know of any requirement for a garage to be framed with treated wood other than the sill plate. I have a friend that has a complaint from someone that has a contractor buddy that was doing some remodeling on their garage claiming that the garage should have been framed with treated wood.

Frank,

Depends on how the garage slab was constructed - and how close the studs are to the ground.

Mitchell Toelle
09-28-2009, 08:14 AM
Jerry,

I thought that any wood in direct contact with concrete needed to be PT. Can you set me straight?

A.D. Miller
09-28-2009, 09:00 AM
Jerry,

I thought that any wood in direct contact with concrete needed to be PT. Can you set me straight?

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 exteriormasonry 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.
[1]This section addresses the need for minimum protection
against decay damage for wood members located
in certain locations.
For those portions of a wood-framed structure that
are subject to damage by decay, the code mandates
that the lumber be pressure-preservative treated or be
naturally durable wood, or be of a species of wood
having a natural resistance to decay. Naturally durable
wood by definition is the heartwood of decay-resistant
redwood, cedars, black locust and black walnut.
Crawl spaces and unexcavated areas under a building
usually contain moisture-laden air. These spaces
must be ventilated in accordance with Section R408 to
remove as much moisture as possible before it causes
decay. Wood placed a minimum specified distance
above grade in unexcavated under-floor areas or
crawl spaces as shown in Commentary Figure
R319.1(1) need not be either preservative-treated
wood or wood that is naturally decay resistant durable
wood. These clearances below floor joists and beams
are deemed to be the minimum necessary to allow adequate
circulation and removal of moisture from the air
and from the wood framing members. Such clearances
apply within the exterior wall line of the building
foundation.
Foundation walls will absorb moisture from the
ground and by capillary action move it to framing members
that are in contact with the foundation. Unless a
minimum clearance of 8 inches (203 mm) is maintained
from the finished grade to wood sills resting on
concrete or masonry exterior foundation walls, decay-
resistant or preservative-treated wood as shown
in Commentary Figure R319.1(2) must be used. The
8-inch (203 mm) clearance specified in this section
has been determined to be large enough to prevent
wetting of wood framing members under most circumstances.
Concrete and masonry slabs that are in direct contact
with the earth are very susceptible to moisture because
of absorption of ground water. This can occur
on interior slabs as well as at the perimeter. In the case
of wood sills or sleepers placed on concrete or masonry
slabs, decay-resistant wood or pressure-treated
wood is required where the slabs are in direct contact
with the ground, as illustrated in Commentary Figure
R319.1(3). Concrete that is fully separated from the
ground by a vapor barrier is not in direct contact with
earth.
A minimum 1/2-inch (12.7 mm) clearance along the
top, sides and ends of wood members projecting into
exterior masonry or concrete walls must be maintained
as illustrated in Commentary Figure R319.1(4),
unless the wood is treated or is of a species that is naturally
decay resistant.
Experience has shown that wood siding may extend
below the sill plate to within 6 inches (152 mm) of the
earth without decaying. Commentary Figure
R319.1(5) shows the required minimum 6-inch (152
mm) clearance from the ground for wood siding,
sheathing and wall framing on the exterior of a building.
It should not be in direct contact with the foundation
wall.

Mitchell Toelle
09-29-2009, 05:36 AM
Thank you Aaron. I've saved that info.

Jerry Peck
10-02-2009, 07:01 PM
SECTION R319
PROTECTION AGAINST DECAY
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.


That's the part I was referring to.