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2018 National Home Improvement Estimator, All Rights Reserved Page 53

Chapter 4, Rough Carpentry

Before bidding a home improvement job, spend a few minutes checking the integrity of the framing.
While wood framing doesn’t just wear out (some wood frame structures in Japan have been in daily use
for over a thousand years), there are destructive organisms that attack wood. Framing that has serious
decay, mold, or termite infestation may be deteriorated past the point of economical repair, and makes
the home more a candidate for demolition than renovation. Financing for home repair may not be
available from conventional lenders when a home has serious structural defects.

Fortunately, the organisms that attack wood can be controlled with wood preservative and by keeping
wood dry. With a little care and attention, nearly any wood-frame structure will reach functional
obsolescence long before the wood deteriorates.

Floor Beams
Figure 4-1 shows the principal components of a framed floor. If the house has a basement, at least one
wood or steel floor beam will support joists under the first floor.

Wood posts that support floor beams should rest on pedestals. Posts embedded in a concrete slab or
foundation tend to absorb moisture and eventually decay. See Figure 4-2. Examine the base of wood
support posts for decay, even if not in contact with concrete. Steel posts are normally supported on
metal plates. Any wood in contact with concrete should be pressure-treated with a preservative such as
ACQ (Alkaline Copper Quat), a product made from recycled copper waste. Use lumber treated with 0.25
pounds of ACQ per cubic foot for applications not in direct contact with the ground. For lumber in direct
contact with the ground, use 0.40 ACQ treated lumber. Use 0.60 ACQ treated lumber for wood
foundation systems.

Decayed beams and sills can be replaced, but it’s slow, difficult work, especially when done in a crawl
space. However difficult the repairs, they may be the only alternative to demolishing the home. Using
temporary needle beams, most homes can be lifted enough to remove weight from the floor beam to
make repairs. Insert a needle beam (6” x 6” or greater) through the foundation wall. Then lift the joists off
the decayed beam with bottle jacks. All lifting in basements and crawl spaces should be done very
slowly to minimize stress damage to the structure. A good rule is to lift no more than 1/4” per day.