If you've found drywood termites, you've probably already heard several different pitches: tent the house, heat it, treat it with orange oil, or just spot treat the damaged area. They don't all work equally well, and the cheapest-sounding option isn't always the cheapest in the long run. Here's how each one really performs.
Fumigation: The Most Reliable Option
Fumigation is the best method for actually eliminating drywood termites, whether you can see them or not. The gas penetrates every piece of wood in the structure, including the framing hidden inside your walls where you'd never find them. That matters because drywood colonies are almost never limited to the spot where you noticed the problem.
It's also worth knowing that by the time you see termite frass (the small, pellet-like droppings), the colony has typically been there for 5 to 7 years. What you can see is rarely the whole picture, which is why treating only the visible spot so often leads to a callback.
Fumigation Pros
- The most reliable way to eliminate drywood termites, seen or unseen
- Reaches every piece of wood in the structure, including hidden framing inside walls
Fumigation Cons
- You'll need to stay elsewhere, so budget for two nights of hotel costs
- If you have a clay or concrete tile roof, you'll usually need to purchase a tile warranty, because some tiles will get broken during the process
Wondering what getting ready for a fumigation involves? This video walks through the preparation steps:
Heat Treatment: A Situational Tool
Heat treatment raises the temperature of the wood high enough to kill termites. The ambient temperature is usually raised to about 160 degrees so that the inside of the walls reaches 140 degrees, which is the kill temperature for insects. It's usually more expensive than fumigation and less reliable, because heat has to reach every infested piece of wood at a lethal temperature, and that's hard to guarantee inside walls and tight framing. That said, it's sometimes the only practical choice. Townhomes, condos, and properties built on a zero lot line can be difficult or impossible to tent, and in those cases heat is a legitimate option.
Heat Treatment Pros
- Kills all insects in the treated area, not just termites
- No hotel stay required
- Can be used on just a single room or the attic
- Works for an apartment, condo, or townhome, where a fumigation requires every owner to agree to it
Heat Treatment Cons
- The most expensive option
- Requires the most preparation: oil paintings can melt, hairspray cans can explode, and ammunition has to be removed
- Can't be used in a home with vinyl flooring, because the heat will destroy it
- Less reliable than fumigation, since every infested piece of wood has to reach a lethal temperature
Here's a look at how a heat treatment works:
Orange Oil: Not What It's Cracked Up To Be
Orange oil is marketed as a natural, low-impact local treatment, but there are a few things you should know before agreeing to it. It's a flammable liquid (the active ingredient, d-limonene, is flammable), and it's a repellent. If it isn't applied perfectly to every gallery, the colony can simply relocate to untreated wood nearby, and you may see the termites come back in a few years.
Orange Oil Pros
- Kills termites on contact
- It has a pleasant orange scent, if you like that
Orange Oil Cons
- It's a local treatment only, so it can't reach termites elsewhere in the structure
- It repels termites, which can push them to move somewhere else instead of eliminating the colony
- Despite the marketing, it's a chemical, not an organic product
- It's a flammable liquid
Local Treatment with Termidor Foam
When the infestation truly is isolated, a local treatment makes sense, and Termidor Foam is a much better choice than orange oil. It's a non-repellent, so termites don't detect and avoid it. They move through the treated wood and carry it back to nestmates, which gives you far better colony-level results than a repellent that just pushes them somewhere else.
The active ingredient in Termidor Foam is spread through the colony by a process called trophallaxis. That's simply the way termites share food and fluids with one another, passing it mouth to mouth or through grooming. Termites that pick up the product pass it along to the nestmates they feed and groom, and those termites pass it on again. The practical result is that the foam doesn't have to reach every termite. Even if it only contacts 20% of the colony, those termites spread the chemical to the rest for us.
Termidor Foam Pros
- No odor
- The home can be treated while you're there, with no need to leave
- It doesn't repel termites
- It uses the termites' own biology to destroy the colony
Termidor Foam Cons
- It's a local treatment only, so it can't account for termites that are still active in other wood members
Bora-Care: A One-Time Preventive Treatment
Bora-Care is applied to bare, open wood such as attic framing. Once it's in the wood, it protects that wood for the life of the wood, so it's a once-in-a-lifetime application. You never need to repeat it unless the wood is replaced. It's an excellent follow-up to fumigation: fumigation clears out what's there now, and Bora-Care on the exposed attic framing helps keep new colonies from establishing afterward.
Which One Is Right for Your Home?
It depends on how far the infestation has spread and the type of structure you have. A detached single-family home with widespread activity is usually a fumigation job. A townhome or condo may call for heat. A small, confirmed, isolated area can be handled with a local Termidor Foam treatment. And in nearly every case, Bora-Care on open wood is a smart addition.
Request a free termite inspection and we'll tell you honestly which option fits your home, not which one is the most expensive.