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Why is the inspector calling out rotten wood on my termite inspection?
Sunday, October 14, 2018
The termite inspection is officially known as a “WDO” in the real estate industry, an acronym for Wood Destroying Organism. The WDO inspection process is strictly regulated by the Florida Department of Agriculture and Consumer Services, and the inspection report must be completed on a state-approved form. Plus, the department is specific as to what organisms that cause wood damage can--and cannot--be included.
While termites are the big menace that most homeowners fear, there are a number of other pests that cause wood damage and must be reported, including several types of wood-boring beetles and the fungi that cause wet wood to rot and crumble. Wood decay may seem like just a nuisance, but advanced decay can cause structural failure and, once the process begins, the affected areas allow more moisture into the structure and the decay accelerates. Replacement wood needed to repair decay damage accounts for 10% of the annual wood production in the United States, according to an Ohio State University study.
How Wood Decay Gets Started
Fungi reproduce by manufacturing single-celled spores, similar to microscopic seeds. Spores are tough; they're able to resist extreme conditions of temperature and humidity and, under adverse conditions, they may go dormant for long periods. Spread primarily by air currents, they collect on horizontal surfaces. Decay fungi feed on the cellulose and lignin of which wood cell walls are composed.
Their hyphae, which are threadlike tubes that penetrate the wood, secrete enzymes which dissolve at least part of the wood cell being fed upon, changing it into a form which can then be absorbed as food. Spores require a moisture content higher than the Fiber Saturation Point (FSP) of the wood species upon which they rest, typically about 30%. Once sufficient water and favorable temperatures are available, spores germinate and develop by extending a hyphal tube. As more spores germinate, fungi multiply to form a colony. Under the right conditions, colonies can expand quickly.
Three Common Types Of Wood Decay
- Brown Rot - This type of decay causes the wood to break down into brown cubes that split against the grain. It is sometimes called “cubic wood rot.” Advanced stages of brown decay result in dry, powdery wood that is unable to support much weight, and crumbles easily.
- White Rot: - This type of decay appears whitish, stringy and mushy, and tends to be more common in hardwoods.
- Dry Rot - A misnomer, this term has been used to describe decayed wood that has since dried and ceased decaying. Some people may erroneously assume that the wood is still in the process of decay. Moisture is required for wood decay to occur, so no literal “dry rot” exists.
The Cure For Wood Decay
Wood decay is located visually by a WDO inspector, then probed with a screwdriver or other blunt probe to confirm that the area has softened. Fixing it is simple: remove and replace the areas of rotten wood. That’s all that is required to get a “clean” follow-up WDO after wood decay fungi damage has been noted by the inspector. In the long term, however, finding a way to avoid the recurrence of wood decay is necessary.
Things You Can Do To Prevent Wood Decay
- Keep wood sealed with a coat of paint in areas of direct weather exposure.
- Avoid installing wood in a configuration where rain water will sit on the surface of the wood for extended periods of time instead of draining away. These spots are called “water traps” in the carpentry trade and professional builders try to avoid them.
- Maintain adequate ventilation in the crawl space under a home. Moisture arising from the soil will create a humid under-floor environment unless adequate cross-ventilation openings are installed.
- Install preservative-treated wood in contact with, or near, the ground.
- Make sure the grading of the soil around your home slopes away from the walls, to avoid water puddling under or next to the home.
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To learn more about TERMITES, WOOD ROT AND OTHER PESTS see these blog posts:
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