Termite products fall into several distinct categories: liquid termiticides applied to soil, bait stations installed around a structure, wood treatments, expanding foams for spot applications, and physical barriers built into foundations. Which products work best depends on the type of termite you’re dealing with, whether you’re preventing or treating an active infestation, and whether you’re hiring a professional or tackling the problem yourself.
Liquid Termiticides
Liquid termiticides are the most established category of termite product and remain the standard for treating subterranean termite infestations. These products are mixed with water and applied to the soil around and beneath a structure’s foundation, creating a continuous chemical zone that termites must pass through to reach the building.
The most effective modern liquids are non-repellent, meaning termites can’t detect them in the soil. Instead of avoiding the treated zone, termites walk through it, pick up the active ingredient on their bodies, and carry it back to the colony. This “transfer effect” is what makes products containing fipronil particularly effective. Fipronil works by blocking a specific type of receptor in the insect nervous system, causing uncontrollable nerve stimulation and death. It binds far more strongly to insect nerve receptors than to mammalian ones, which is part of why it’s approved for use around homes.
Liquid treatments create a protective barrier almost immediately after application. Termites that contact treated soil begin dying within hours, and the transfer effect can spread the chemical through a colony over the following weeks. This speed is a major advantage over bait systems.
Bait Stations
Termite bait stations take a different approach. Plastic stations are installed in the ground at regular intervals around a structure’s perimeter, each containing a cellulose material laced with a slow-acting growth inhibitor. Foraging termites find the bait, feed on it, and share it with nestmates back in the colony. The active ingredient prevents termites from successfully molting, gradually collapsing the colony’s population.
The trade-off is time. Weeks or months may pass before termites discover the bait underground and distribute it to enough nestmates. The full elimination process can take several months or longer, and some feeding and structural damage may continue before the bait takes effect. Bait systems work best as long-term monitoring tools or as a complement to liquid treatments rather than a standalone emergency response to an active infestation.
Foam Products for Spot Treatments
Expanding foam termiticides fill a gap that liquids and baits can’t reach: wall voids, ceiling cavities, and other enclosed spaces where termites are actively feeding. These products expand at ratios around 30:1, meaning a small amount of liquid generates enough dry foam to coat the inside of a wall cavity and distribute the active ingredient across surfaces termites are using.
Foam is especially useful for drywood termites, which live entirely inside the wood they’re eating and never contact the soil. For drywood infestations limited to a few boards or a small area, foam injection can eliminate the colony at a fraction of the cost and disruption of whole-structure fumigation. The foam can be sprayed directly onto interior infestation sites, into wall voids, or on exterior elements like decks, fencing, and wooden retaining walls. If activity persists, retreatment is possible 30 days after the initial application.
Borate Wood Treatments
Borate-based products are applied directly to wood rather than soil, making them a prevention-focused option typically used during construction or renovation. They’re available as spray-on solutions applied to framing lumber after the structure is framed but before insulation goes in, or as pressure-treated lumber where the borate is forced deep into the wood at a mill.
When applied topically with a sprayer, borate penetration is generally limited to the outer 5 millimeters of the wood after eight weeks of diffusion, regardless of the solution used. Deeper penetration (beyond 11 millimeters, covering over 70% of the cross section) requires sustained high moisture levels in the wood over 26 weeks, conditions that don’t typically exist in a finished building. That shallow penetration sounds like a weakness, but USDA Forest Service research notes that there have been few reports of termite damage in structures topically treated with borates, even under a wide range of conditions. The reason: foraging termites are unlikely to find small breaks in a treated wood surface when the surrounding area is thoroughly coated with high concentrations of borate.
Borates do have one significant limitation. They’re water-soluble, which means they can leach out of wood exposed to rain or ground moisture. This makes them best suited for interior framing and other protected applications where the wood stays dry.
Physical Barriers
Physical termite barriers are installed during construction and work by creating a gap or obstacle that termites physically cannot cross. They require no chemicals and don’t degrade over time, making them essentially permanent.
Stainless steel mesh is one option. The mesh uses grade 304 or 316 wire with openings no larger than 0.66 mm by 0.45 mm, small enough that termites cannot squeeze through. It’s installed around foundations, under concrete slabs, and around utility penetrations where pipes and wires enter the building.
Particle barriers use a different principle. Crushed basalt or graded sand is installed in a layer 3 to 4 inches deep around foundations, in wall cavities, or beneath slabs. The particles are sized so that each one is too large for termites to carry away, while the gaps between particles are too small for termites to crawl through. The required particle size varies by species: 1.2 to 1.7 mm diameter for western subterranean termites, 1.7 to 2.8 mm for eastern subterranean termites, and 1.7 to 2.4 mm for Formosan termites. The stone must have a specific gravity of at least 2.52, dense enough that termites cannot move the particles.
Choosing Products by Termite Species
The type of termite dictates which products are appropriate. Subterranean termites nest in the soil and build mud tubes to reach wood above ground. Liquid soil treatments and bait stations target this behavior directly, intercepting termites along their foraging routes. These are the products most homeowners think of when they hear “termite treatment.”
Drywood termites are a completely different problem. They live inside the wood itself, never touching soil, so soil treatments and bait stations are irrelevant. Drywood infestations require either localized treatments (foam injection, spot heat application, microwave devices, or high-voltage electrocution tools that kill termites inside the wood) or whole-structure treatments. Whole-structure options include fumigation with sulfuryl fluoride, which kills drywood termites within several days, or heat treatment, which involves raising all wood in the structure to at least 120°F and holding that temperature for a minimum of 33 minutes.
Dampwood termites are the simplest to address. They require high-moisture wood to survive, so the primary “product” is actually a repair: fix the water leak, replace the damaged wood, and the problem resolves itself without chemical treatment.
DIY Products vs. Professional Products
The gap between what you can buy at a hardware store and what a licensed technician uses comes down to a single regulatory distinction. Under the Federal Insecticide, Fungicide, and Rodenticide Act, the EPA classifies every registered pesticide as either general use or restricted use. General-use products are available over the counter to anyone. Restricted-use products can only be purchased and applied by someone with a state-issued applicator certification, because they carry higher risk if handled without training.
That classification is the actual difference between a $15 can of termite spray and a professional treatment. The safety margin built into general-use products caps both their strength and their longevity. A consumer foam spray might kill termites on contact in a visible spot, but it won’t deliver the transfer effect or residual soil protection of a professional-grade non-repellent termiticide. Professional applicators also have access to specialized equipment for subslab injection, deep soil trenching, and precise foam delivery into wall cavities, application methods that matter as much as the chemical itself.
DIY bait stations and borate sprays are the consumer products with the most realistic chance of meaningful impact. Bait stations placed around a home’s perimeter can intercept foraging subterranean termites over time, and borate solutions sprayed on exposed framing during a renovation provide genuine long-term protection. For an active infestation, particularly subterranean termites with established mud tubes and visible damage, consumer products are unlikely to reach the colony’s core the way a full perimeter liquid treatment would.
Prevention Products vs. Treatment Products
Prevention and treatment overlap but aren’t the same. Physical barriers (mesh, particle systems) and borate wood treatments are purely preventive, installed during construction before termites arrive. Liquid termiticides serve both roles: they eliminate active colonies and create a lasting barrier that prevents reinfestation for years. Bait stations function as ongoing monitoring and suppression, catching new colony activity before it becomes a structural problem.
For new construction in termite-prone areas, combining a physical barrier with borate-treated framing lumber provides chemical and non-chemical layers of protection. For existing homes, a liquid perimeter treatment supplemented with bait station monitoring covers both immediate elimination and long-term detection. Foam products fill the role of targeted intervention when termites are found in a specific, accessible location.