What to Expect

What to Expect From Whole-Structure Fumigation

In a whole-structure fumigation, the building itself becomes the treatment vessel: tented and sealed, filled with a fumigant gas that penetrates every joint, beam, and framing void, then aerated and cleared before anyone re-enters. It is the most thorough option for widespread drywood termite infestations — and a regulated process from the first inspection through preparation, tenting, aeration, and re-entry clearance.

Why Drywood Termites Are So Hard to Reach

Drywood termites live entirely inside the wood they consume — no soil contact, no mud tubes, no outside water source. A single structure can hold multiple disconnected colonies at once, each excavating its own gallery system inside framing, eaves, window trim, and wall voids. Because they hollow wood from the inside out, most of an infestation is invisible from the surface; the evidence a homeowner notices is usually a small fraction of what is actually present. Localized treatments can reach a known gallery, but they cannot reach colonies nobody has found. That is the problem fumigation exists to solve: a gas fills the entire sealed structure and penetrates every joint, beam, and cavity — including the ones no inspection can physically open.

Signs of Infestation and What an Inspection Looks For

The classic drywood evidence is frass — dry, six-sided fecal pellets pushed out of small kick-out holes in the wood — along with discarded swarmer wings near windows and doors, hollow-sounding wood, and blistered or bubbling paint over wood surfaces. A professional inspection is less about confirming that termites exist and more about mapping how widespread the evidence is. Inspectors work through attic framing, eaves, window and door trim, the garage, and the subarea, probing wood, distinguishing old evidence from active infestation, and noting areas that cannot be accessed directly. For real-estate transactions this becomes a WDO report. The scope finding — evidence in one location versus many — is what drives every treatment decision that follows.

How the Treatment Decision Gets Made

Not every drywood termite finding calls for tenting. When infestation is localized and accessible, direct wood treatment can often address it without vacating the home. Fumigation enters the picture when evidence appears in multiple locations, when prior spot treatments have not resolved activity, or when infestation sits in areas that cannot be reached at all. Fumigation itself is not a do-it-yourself option in any form: it uses a restricted fumigant — Vikane (sulfuryl fluoride) is the industry standard — that only licensed operators may handle, and it requires gas-concentration calculations based on the structure's volume, sealed tenting, monitoring during exposure, and clearance testing that California requires before anyone re-enters. The professional difference is not just equipment; it is a regulated process from start to finish.

Our Process

How It Works, Step by Step

Sizing Up the Spread
The process starts with a conversation about what you have seen — pellets, discarded wings, prior inspection reports — along with the structure's age, size, and any earlier treatments. This helps establish whether the evidence points toward a localized issue or something that may involve multiple areas of the framing.
The Pre-Fumigation Inspection
An inspector examines the structure: attic, accessible framing, eaves, window and door trim, garage, and subarea. They document where evidence appears, assess whether activity looks current or old, measure the structure — fumigant dosage is calculated from the building's volume — and flag any areas that cannot be accessed directly.
The Recommendation: Spot Treatment or Tent
You receive written findings describing what was found and where. If evidence is confined to accessible areas, a localized treatment may be discussed instead; if it appears in multiple or unreachable locations, whole-structure fumigation is generally the recommendation. The reasoning behind the recommendation should always be explained, not just asserted.
Preparation, Tenting, Aeration
A preparation checklist is reviewed in advance: food and medications are bagged or removed, and all people, pets, and plants leave the structure. The building is then tented and sealed, the fumigant is introduced and monitored, and the structure is aerated. The full cycle typically spans a few days; timing varies by property.
Clearance Testing and Re-Entry
Re-entry happens only after clearance testing confirms fumigant levels are below California's re-entry threshold. Documentation of the completed treatment follows — useful for real-estate files. Because fumigation leaves no residual protection in the wood, periodic inspections afterward are the practical way to catch any future colony while it is still small.

Local Knowledge

Why Fumigation Comes Up So Often on the Central Coast

The western drywood termite (Incisitermes minor) is the dominant structural termite in older coastal homes across Monterey and Santa Cruz counties. The Mediterranean climate works in its favor: mild winters never knock colonies back, and decades of exposure let the older wood-frame housing stock in places like Pacific Grove, Carmel, and Santa Cruz accumulate multiple disconnected colonies over time. Drywood swarmers fly in late summer through early fall — typically August through October, on warm evenings after a stretch of heat — landing on the same weathered structures year after year. When an inspection of a decades-old coastal home finds evidence in several separate areas, that pattern of many small colonies rather than one large one is exactly the situation whole-structure fumigation was designed for.

Common Questions

Good to Know

How long is a home typically vacated for fumigation?

A typical residential fumigation spans roughly two to three days from tenting to cleared re-entry: the structure is tented and the fumigant introduced, the concentration is held and monitored, then the building is aerated and tested. The exact timeline depends on structure size, temperature, and site conditions, so specifics are confirmed during planning for your property. Everyone — including pets and plants — stays out until clearance testing authorizes re-entry.

What preparation does fumigation involve?

Food, medications, and pet food are either removed from the structure or sealed in special fumigation bags, and all people, pets, and plants leave for the duration. Arrangements are also generally made for gas service shutoff and property access. A detailed preparation checklist is reviewed with you in advance during the pre-fumigation inspection, and the exact requirements can vary somewhat by property and situation.

Does fumigation protect against future termites?

No — and the distinction matters. The fumigant penetrates the structure as a gas and then dissipates completely during aeration, which is why belongings do not need to be discarded afterward, but it also means no residual barrier remains in the wood. New drywood swarmers can land on and enter a structure in later seasons. Periodic inspections are the practical follow-up, since catching a new colony early keeps treatment options simpler.

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