Termite Treatment Options: Soil Treatments, Baits, Fumigation and More

You have confirmed termites, or an inspector says you have them, and now you are looking at a proposal full of unfamiliar terms. This guide explains each common treatment in plain language, which termites each one suits, how disruptive it is and what follow-up it needs. It also covers warranties and the questions to ask before you sign. If you have not confirmed termites yet, start with the signs of termites.

First, match the treatment to the termite

The type of termite decides the treatment. Subterranean termites, including Formosan termites, nest in the soil, so treatment targets the soil around and under the house. Drywood termites live entirely inside the wood, so soil treatment does nothing for them. The main termites guide has a table to help you tell them apart.

Termite treatments compared

Liquid soil termiticides

Liquid treatments are still the most common way to control subterranean termites. A typical job puts a large volume of diluted termiticide into the soil along the foundation, under concrete slabs and inside foundation walls. Technicians use masonry drills, large spray tanks and long rods to inject soil.

Repellent vs non-repellent. Older termiticides repelled termites. Termites sensed the treated soil and avoided it, then often found an untreated gap and kept feeding. Today’s products are mostly non-repellent. Termites cannot detect them, so they tunnel into the treated zone and die. Extension specialists say non-repellent products are more likely to work the first time. Active ingredients you may see on a proposal include fipronil, imidacloprid and chlorantraniliprole.

Applied according to the label, liquid termiticides are meant to protect for at least five years. A soil treatment protects the structure, but it is not designed to wipe out the whole colony out in the yard.

Bait systems

With baiting, a company places stations in the soil around the house. Some systems also allow stations indoors over active mud tubes. Termites find the bait, eat it and share it with the colony. The slow-acting insecticide reduces or eliminates the colony over time.

Baits have real advantages: little or no drilling, much less pesticide overall and an option for homes where liquids are hard to apply, such as near wells. The trade-offs:

• They are slow. Termites may take weeks or months to find the stations and months more to be controlled. Cold, frozen, flooded or very dry soil slows things down.
• They need upkeep. Bait leaves no residual barrier in the soil, so protection depends on keeping the stations checked and stocked.
• Some damage may happen first. If you have a heavy infestation or a home sale coming up, you may want a liquid treatment instead of baits or alongside them.

Borate wood treatments

Borates are wood treatments applied to bare wood, often during new construction. The label calls for treating wood from the foundation up to at least two feet. Borates may not soak deep enough to protect the center of thick lumber, and some termite species do not respond to them, so extension specialists recommend them alongside other treatments rather than as the only one.

Drywood termites: spot treatment, fumigation or heat

Localized treatments. A licensed applicator drills small holes into infested wood and injects a liquid, foam or dust into the galleries. Nonchemical spot methods also exist. Spot treatment works when the colony is accessible and accurately located. The problem is that drywood colonies are hard to find, and treating one colony can miss others hidden in walls. Results also vary by applicator. Replacing a small piece of infested wood is another option.

Fumigation. The whole building is covered with tarps and filled with a gas fumigant, usually sulfuryl fluoride. The gas reaches every infestation, including ones no one has found. University of Florida specialists describe it as a reset for drywood termites. Fumigants are restricted-use pesticides and heavily regulated. Everyone, including pets and plants, must leave for several days, gas pilot lights must be turned off, and tarps dragged across a roof can damage it.

Heat. Heaters raise infested wood to at least 120°F and hold it there. Heat uses no chemicals and finishes in hours. Large beams heat slowly, and wood resting on concrete or tile can stay cool enough for termites to survive. Heat can damage sensitive items, which need to come out first.

Neither fumigation nor heat leaves residual protection.

Why DIY soil treatment usually falls short

Store-bought termite products almost never solve an established infestation in a house. A proper soil treatment needs a lot of termiticide placed exactly right around and under the whole foundation, often through slabs and inside foundation walls. Missing a gap leaves a path open. Many entry points are hidden and need knowledge of how the house is built. EPA advises that in most cases a trained professional should apply termiticides, and improper application can contaminate the home or a nearby drinking water well. The one reasonable DIY case is a small wooden item not attached to the house, which you can treat or throw out.

What you can do yourself is fix the conditions that invite termites, such as wood touching soil and moisture at the foundation. The termites guide covers those steps.

Ask to see the product label. EPA advises that a termiticide should only be used on your home if its label includes directions for termite control. Ask the company which product it plans to use and when you can safely go back into treated areas. Our page on using pesticides safely explains how to read a label.

Warranties and service contracts

Most termite work comes with a warranty or a renewable service contract. They differ more than most people expect, so read the terms before you choose.

• Retreatment only. The most common type. If termites come back, the company retreats the affected area at no extra charge, as long as you keep renewing the contract each year.
• Retreatment plus repair. Some companies also pay to repair new termite damage. Figuring out when damage happened is hard, so read exactly what counts as covered.
• What voids a warranty. Moisture problems, plantings placed against the house and spray foam insulation that blocks inspection can void coverage or keep a company from offering one. Ask for the list in writing.
• When no warranty is offered. A company may decline to warrant a home with a well, drains or a crawl space it cannot reach. Spot treatments are often not warranted at all.
• Bait contracts. Ask how often stations are checked, what the renewal includes and whether stations stay in place after the first contract.

Get more than one inspection

Getting inspections and written proposals from two or three licensed companies helps confirm the infestation and lets you compare methods and warranty terms. Termites damage wood slowly, so taking a few extra weeks to decide rarely matters. Be wary of anyone who pressures you to sign on the spot.

Questions to ask each company:

1. Are you licensed by the state agency that regulates termite work? Can I see the license?
2. What type of termite do I have, and where is the activity?
3. Which treatment do you recommend, and which product will you use?
4. Will you drill through slabs, porches or interior floors?
5. How long until the termites are under control, and how will you confirm it?
6. What does the warranty cover, how long does it last and what voids it?
7. Who will do the work, and how much experience do they have?
8. Can you give me references?

For more on vetting companies, see choosing a pest control company.

Termite treatment questions

Do I need to leave the house during treatment? For a soil treatment or baits, usually not, but ask about re-entry times for treated areas. For fumigation, yes: everyone, including pets, leaves for several days.

Can baits and liquids be used together? Yes. Some companies add a partial liquid treatment to a baiting program, especially when termites keep feeding.

Does treatment fix the damage? No. Treatment stops termites. Damaged wood still needs to be inspected and, if weak, repaired or replaced by a contractor.