WDO Inspection Guide for North Bay Property Owners

What Is a WDO Inspection?

A Wood Destroying Organism (WDO) inspection is a licensed examination of a structure for evidence of termites, wood-boring beetles, wood-decay fungi (dry rot), and the conditions that make each of these likely to develop. In California, WDO inspections must be conducted by a licensed Structural Pest Control Company holding an OPR (Operators and Pest control Regulations) license. The written WDO report is the standard document required by virtually all North Bay lenders as a condition of financing and is accepted by all title companies, escrow officers, and real estate institutions in Sonoma, Marin, Napa, and Solano Counties.

What Is Inspected During a WDO Inspection

A complete WDO inspection covers all accessible areas of the structure: the exterior perimeter (foundation walls, crawl space vents, exterior wood surfaces, roofline and eaves); the crawl space (sill plates, floor joists, subfloor, posts and beams, moisture conditions); the attic (roof framing, top plates, attic floor framing); and the interior (baseboards, window sills, under sinks, accessible wall framing, and any other visible wood surfaces). All findings are noted on a property diagram included with the report.

Understanding Section 1 and Section 2

California WDO reports are divided into two sections:

• Section 1 — Active infestations and conditions requiring immediate correction. This includes active termite infestation, active wood-decay fungus, evidence of current wood-boring beetle activity, and any other condition that represents a current infestation. Most North Bay lenders require all Section 1 items to be corrected before close of escrow
• Section 2 — Conditions that are not currently infested but that create elevated pest risk. This includes wood-soil contact, inadequate crawl space ventilation, moisture conditions, and other conducive conditions. Section 2 items are recommended for correction but are typically not required by lenders
• The report also indicates findings that require further inspection — conditions where the inspector cannot fully assess the extent of damage or activity without additional access or opening of walls

Who Orders the WDO Inspection?

In North Bay California real estate transactions, the WDO inspection is most commonly ordered by: the listing agent before listing (a pre-listing inspection allows sellers to address issues before buyers see them); the buyer\'s agent after acceptance (the WDO inspection is a standard contingency in most North Bay purchase contracts); or the lender (some lenders require a clean WDO report independently). The party responsible for the cost of the inspection and correction of Section 1 findings is a negotiated element of the purchase contract — both arrangements (seller-paid and buyer-paid) are common.

How Long Does a WDO Inspection Take?

A typical North Bay single-family home inspection takes 45–90 minutes. Larger properties, properties with complex crawl spaces or multiple accessory structures, and very old homes may take 2–3 hours. Redwood Empire delivers WDO reports the same day as the inspection in most cases — meeting the tight timelines of North Bay escrow transactions.

WDO Report Validity

California WDO reports do not have a statutory expiration date, but most lenders and escrow officers require a report issued within 30–90 days of the close of escrow. If significant time has passed since the inspection or if substantial rain has occurred (which can trigger subterranean termite activity), a re-inspection may be warranted before close.

Frequently Asked Questions