Understand exactly what a licensed termite inspector examines, what they are looking for in each area, and what a professional WDO report tells you about your property.
A professional termite inspection — also called a Wood Destroying Organism (WDO) inspection — is a systematic visual and probe examination of a structure for evidence of termite activity, wood-boring beetle activity, wood-decay fungus (dry rot), and conditions that make each more likely. In California, WDO inspections must be conducted by a licensed Structural Pest Control inspector holding an OPR license. The report produced is the standard document accepted by all North Bay lenders, real estate institutions, and title companies.
The exterior inspection examines the entire structure from the outside before entry. Inspectors assess the foundation walls and grade for mud tubes, wood-soil contact, and moisture staining; crawl space vent screens and access panels for condition and gaps; all exterior wood surfaces including window frames, door frames, fascia, soffits, and trim (probed for hollow areas and checked for frass); and the roofline and eaves from the ground for conducive conditions.
The crawl space is a high-priority inspection area. Inspectors probe foundation sill plates (the most common subterranean termite target), floor joists and subfloor throughout accessible areas, and support posts and beams. They use moisture meters to assess wood and soil moisture levels, check plumbing penetrations for leak-driven moisture, evaluate vapor barrier condition, and note any evidence of previous treatment or repair work.
Drywood termites most commonly establish in attic framing. Inspectors probe roof rafters, ridge boards, collar ties, and top plates along their full accessible length; look for frass accumulations in insulation and on top plates indicating active infestation above; and assess roof sheathing condition for moisture staining and decay.
The interior inspection covers all accessible wood surfaces throughout the living area. Inspectors probe baseboards and window sills (particularly on exterior-facing walls); inspect under sinks and near plumbing for moisture-driven conducive conditions; assess hardwood flooring for buckling or blistering; check accessible wall framing in unfinished areas like garages; and inspect wood-framed fireplaces and hearths.
A California WDO report categorizes findings into Section 1 (active infestations requiring correction before most lenders will fund a purchase) and Section 2 (conditions conducive to future pest activity — recommended but typically not lender-required). The report includes a diagram of the structure showing the location of every finding and specific recommendations for treatment and repair.
Licensed WDO inspections and structural pest reports for North Bay real estate.
Learn More →Localized treatment, soil barriers, and structural fumigation.
Learn More →Official WDO reports accepted by all North Bay lenders.
Learn More →Structural tent fumigation for widespread drywood termite infestations.
Learn More →In-house repair of termite-damaged structural wood.
Learn More →Same-day and next-day appointments available throughout Sonoma, Marin, Napa, and Solano Counties.