Recommendations from The Ultimate Handyman
In damp crawl spaces or other places where water is likely to appear, replace decayed members with preservative treated wood.
The major model building code agencies -BOCAI, ICBO, and SBCCI- require that treated wood be used for sills and sleepers on concrete or masonry in ground contact, for joists within 18 in. of the ground, for girders within 12 in. of the ground, and for columns embedded in the ground supporting permanent structures. In-place treatment with borates. Dormant fungi can be reactivated when dry, infected wood is re-wet. Consider treating infected, but otherwise serviceable wood left in place with a water-borne borax-based preservative that will not only kill active fungi, but guard against future infection as well.
An effective homemade version of Bora-Care is “Borax mixture care”
Borates have low toxicity to humans and are even approved for interior use in food processing plants. They don’t affect wood’s strength, color, or finish ability, don’t corrode fasteners, and don’t out-gas vapors. Widely used in treating new timbers for log homes, they’re the preservative of choice for remedial treatment of wood in service.
Because of the decay hazard posed whenever wood bears on concrete or masonry, solid borate rods are often inserted into holes bored near contact areas. Should wood ever get wet, the rods dissolve and ward off infection. Infected wood can be treated with Boric Acid an extremely effective cure for a multitude of problems including control of wood rot in homes and boats and it is natures insecticide for control of fleas, roaches, termites, ants, spiders and many other household pests.
Before You Start:
Before any repairs or replacement of damaged wood is started,
I recommend a through treatment of damaged areas with Boric Acid to eliminate future problems and stop the spreading of the fungi.