Termite Wood Treatment Services

Termite wood treatment applies termiticide compounds or physical barriers directly to wood members — framing, joists, sills, and finish lumber — rather than to the surrounding soil. This page covers the primary treatment categories, their chemical and mechanical mechanisms, the structural and regulatory frameworks that govern their use, and the decision logic for matching treatment type to infestation scenario. Understanding these distinctions matters because wood treatments operate under separate EPA registration pathways and state pesticide licensing rules than soil-applied liquid termiticides.

Definition and scope

Wood treatment for termite control is a targeted intervention strategy in which termiticides or boron-based compounds are applied at the wood surface or injected into wood members to kill active termites, establish a toxic or repellent zone within the wood fiber, or prevent future colonization. The scope spans both preventive applications made during construction and remedial applications made to existing structures with confirmed or suspected infestations.

The EPA registers termiticide products under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). Any wood treatment product applied by a pest control operator must carry an EPA registration number specific to the wood-application use pattern — a product labeled only for soil use cannot legally be applied to wood members. Applicators are also required to hold state-issued pesticide applicator licenses; licensing requirements vary by state but are enforced under the authority of state departments of agriculture operating in coordination with EPA under FIFRA Section 26. A full breakdown of licensing structures appears at Termite Control Service Licensing Requirements US.

Wood treatment differs from liquid termiticide treatments applied to soil in a foundational way: soil treatments create a chemical barrier between the colony and the structure, while wood treatments render the wood itself inhospitable or lethal. The two approaches are often used together as part of an integrated treatment plan.

How it works

Wood treatment products function through three distinct mechanisms:

Contact toxicity — The termiticide (e.g., bifenthrin or permethrin formulated for wood application) kills termites that tunnel through treated wood by disrupting their nervous systems via sodium channel interference.
Systemic diffusion — Borate-based products (disodium octaborate tetrahydrate, sold under product names like Tim-bor and Bora-Care) penetrate wood fiber and diffuse through the cell structure. Termites ingest borates during feeding, which inhibits metabolic enzymes and causes colony mortality.
Repellency — Certain pyrethroid-based wood treatments create a repellent zone that redirects termite foraging without necessarily providing direct kill, which can be advantageous in localized spot treatments.

Borate penetration depth depends on wood moisture content. The USDA Forest Products Laboratory has documented that disodium octaborate tetrahydrate penetrates effectively when wood moisture content exceeds 30%, but penetration into dry lumber below 19% moisture content is significantly limited. This moisture dependency is a primary selection criterion for choosing between borate and non-borate wood treatments.

Injection treatments deliver concentrated termiticide directly into galleries or voids in infested wood members through drilled ports, typically spaced at 10–12 inch intervals. This method is governed by product label instructions, which under FIFRA carry the force of law.

Common scenarios

Preventive pre-construction treatment: Lumber is sprayed or dipped with borate solution before installation. This approach is common in high-risk subterranean termite zones (USDA Termite Infestation Probability Zones 1 and 2, covering most of the southern United States). The International Residential Code (IRC) Section R318 identifies approved wood preservative treatments for termite-prone areas and references standards from the American Wood Protection Association (AWPA).

Remedial spot treatment of active infestations: When signs of termite infestation are localized — a single wall cavity or a crawl space joist run — applicators may inject termiticide into galleries and treat accessible wood surfaces, avoiding the cost and disruption of full-structure fumigation.

Crawl space and subfloor treatment: Wood members in crawl spaces are among the most frequent targets for wood treatment, particularly in structures with persistent moisture problems. The connection between moisture conditions and termite activity is direct; moisture control and termite prevention addresses the environmental modification strategies that complement wood treatment in these spaces.

Historic and architecturally sensitive structures: Buildings where fumigation is impractical due to structural complexity or occupancy constraints are candidates for borate wood treatment as a less disruptive alternative. The National Park Service Preservation Brief 45 addresses pest management in historic structures and recognizes borate treatments as a preservation-compatible option.

Decision boundaries

Not every infestation or risk scenario warrants wood treatment as the primary response. The table below outlines the key comparison between borate-based and pyrethroid-based wood treatments:

Criterion	Borate-Based (e.g., disodium octaborate)	Pyrethroid-Based (e.g., bifenthrin wood formulations)
Primary mode	Ingestion toxicity, systemic diffusion	Contact toxicity, repellency
Moisture dependency	High — requires wood MC >19% for penetration	Low
Drywood termite efficacy	Effective	Effective with direct contact
Subterranean termite use	Preventive and remedial	Typically spot remedial
Re-entry interval	Product-label dependent	Product-label dependent

Wood treatment alone is insufficient as the sole strategy against subterranean termites when colony populations are large, because the colony's primary mass remains in soil. In those cases, termite bait station systems or termite soil treatment services are the structural complement. For drywood termites with widespread infestations, termite fumigation tenting services may be indicated where wood treatment cannot achieve the penetration depth required.

Applicators must follow EPA-registered label instructions precisely — including application rates expressed in grams of active ingredient per board foot or percent solution concentration — because the label constitutes a legally binding use restriction under FIFRA.

References

📜 2 regulatory citations referenced · 🔍 Monitored by ANA Regulatory Watch · View update log