TL;DR Summary

  • Tenting/fumigation is the only 100% effective treatment for drywood termites
  • Clearance” does not mean the property has no termites.
  • If termites are found during escrow, have the seller tent the property while in escrow. Hire your own termite inspector to review the findings of the seller’s inspector (most inspectors do the assessment for free). Keep them around to review any wood repairs.
  • HOAs complicate things, if you have one, check the HOA’s rules

Congratulations on buying a home. It’s an exciting time with thousands of details that need to be worked out. It’s easy, even required, to gloss over some details simply because there isn’t enough time to manually check everything. I’m here to tell you that termites are not a detail to gloss over.

I bought a home that was “treated” for termites and then “cleared”. Three weeks after escrow closed and I moved in, I found more termites and had to pay to get my house treated. Over a year later I’m getting my house tented. I would like what I’ve learned to help someone else buying a house.

In some states, termite treatment is mandated by law. In California there is no such termite law, but almost every mortgage requires that the property is “cleared” for termites before escrow will close. But a clearance simply means that a termite inspector could not find evidence of any live termites - which actually can be very different than there not being any live termites. I’ve had termite inspector professionals tell me that none of them want to blow an escrow, and since they are hired by the seller they have a financial incentive to make the “clearance” easy.

The Single Most Important Thing to Know About Buying a Property with Termites

If you are buying a house with termite activity, and your goal is to move into a house with zero termites, have the seller tent the property during escrow, even if the termite activity is not substantial. Do your best to avoid local treatments - especially orange oil treatment. Drywood termites are incredibly difficult to detect; there is no modern technology which can detect them easily (despite sales pitches otherwise). When you finally do see signs of a termite presence, it is usually just the tip of the iceberg. And the only 100% effective way to kill termites is to tent the building (fumigate) with sulfuryl fluoride (aka Vikane). Because termite colonies are impossible to map, local treatment is ineffective because you’re very likely only treating part of the infestation.

Tenting with Sulfuryl Fluoride

A common misconception about tenting is that the gas will leave a poisonous residue behind. This is not true. Sulfuryl fluoride is a true physical gas; it is not a vapor or suspension. Just like carbon dioxide or oxygen, when it leaves a container it leaves no trace behind. This is why you don’t even have to wash your silverware or dishes after your house has been tented. You do however, have to seal any food or liquid that you, or your pets, might eat or drink after the fumigation.

How Sulfuryl Fluoride Is Poisonous

When a human or animal is exposed to sulfuryl fluoride, they get fluoride poisoning which can be fatal. This is why you, your pets, and even your plants must evacuate a building before it is gassed. Food and water can absorb fluoride from sulfuryl fluoride - this is why you have to seal all comestibles in airtight containers before tenting. There has been research on this, and there is no connection between sulfuryl fluoride and cancer. If you’re not around the building while it’s tented you shouldn’t have anything to worry about. Even if there were ill effects from Sulfuryl Fluoride, so long as you’re nowhere near the treated property until (well after, to be safe) ventilation then you’re not inhaling any more Sulfuryl Fluoride than the minute amount already in the atmosphere (and you’re breathing anyway).

Sulfuryl Fluoride gotchas

Any half-decent tenting crew is trained to look for a few things that could potentially end up with a human being accidentally poisoned. The one that surprised me the most is water-proof mattress covers. Normally sulfuryl fluoride disperses quickly, but it can be trapped in semi-air-tight containers like a water-proof mattress pad. The crew should check for such items, double-check for unsealed comestibles, and correct any mistakes before tenting.

Heat Treatment

While in theory heat treatment is effective, it is almost never effective in practice. In order for heat treatment to be effective the center of every piece of wood in the house’s frame needs to reach 120°F for at least 33 minutes. This means that the ambient temperature is going to be significantly higher. I have been told by pest controllers that getting an entire structure to this temperature is impossible. And even if the building could be heated that high the heat would melt plastics, potentially destroying wiring, plumbing, and bubbling the paint.

Local Treatments


If you must get local treatment, some are more effective than others. The most effective treatment is Termidor, which not only kills termites but the poison is transmitted between termites. So termidor gives you a chance (not at all a guarantee) that a local treatment can spread to the rest of the colony and eliminate it. Though it is not obviously harmful to humans, in my opinion you want to limit your exposure to termidor as much as possible. Human exposure to termidor has not been studied well enough to understand yet.

Orange Oil (XT-2000)

An all natural product, mostly made of d-limonene. This seems to be sold to people scared of fumigation. I imagine these people tend to be more likely to buy organic and read New Age books (not a dig at their lifestyle, I tend to buy organic myself). Unfortunately scientific research on orange oil indicates it is entirely ineffective at termite abatement.

I actually had Xtermite, a company that specializes in treating termites with orange oil, inspect my house. I asked the inspector/salesman for scientific evidence that orange oil is effective. He could only point me to testimonials and the blog articles of an exterminator who uses orange oil. Testimonials are one of the first-used tools of a conman, and a blog article is not exactly scientific proof. He did not reply to my last email asking him to supply me with a peer-reviewed scientific article. I give orange oil two thumbs down.


Everything else that exterminators try to sell: electric-shock, other chemicals, borascopes, infrared, etc. This stuff is all bunk and doesn’t actually work.

Preventative Treatments

Tim-bor and Boracare are both fairly effective preventative treatments created from a type of salt (Disodium Octaborate Tetrahydrate), this is a natural product. Tim-bor is sprayed onto the surface of wood, or wood can be treated with boracare which seeps into the wood. Termites do not enter wood coated with these products and so you may want to consider having the wood sprayed in attics or underneath the home.

Termites and HOAs

The relationship between termites and HOAs is complicated. Most HOAs have a clause in the CCRs that states they are responsible for treating termites. Please read your HOA rules to see which, or contact the HOA and ask.

If your HOA is responsible for treating termites.

Your HOA has total control over your termite treatment. A high-level court case recently decided that a home owner cannot overrule the HOA when it comes to termite treatment. That means that if the HOA wants to fumigate and you don’t, you are out of luck. Or if the HOA will only do local treatments and you want tenting, you are out of luck. You should contact your HOA to see what method of termite treatment they use.

If your HOA is not responsible for treating termites

Good news, you get to do what you want. Unless you share a wall with one or more neighbors…

Termites and neighbors with shared walls

Tenting cannot be done on a fraction of a building. So if you have neighbors that share walls with you, your neighbors also need to be tented if you want to get tented. This is a huge hassle because almost inevitably some neighbors are strongly against what other neighbors are for - especially as the number of neighbors with shared walls increase. Your HOA might mandate how neighbors are supposed to treat termites and share the costs so check the rules.

If you want a neighbor to tent and they refuse, it is my non-expert and non-legal belief that they are legally liable to maintain their property such that the value of your property is not degraded. However it might take a very un-neighborly lawsuit to settle it; definitely something to avoid.

Finding When a House Was Previously Inspected

States may manage a database that detail when a property was inspected for termites.

In California, the SPCB maintains a termite inspection database for the previous two years. Sometimes I love what my tax dollars do.

Getting quotes for treatment

If, unfortunately, you did not get the seller to tent for termites and you need to get a company to tent your property, my biggest piece of advice is to get multiple quotes. In my recent experience, prices vary wildly. The quotes I received ranged from $2400 to about $4000. I found that the big-name companies tended to be more expensive, so be sure to get some small companies out there too that get good online reviews. Make sure your termite inspector is licensed and check to see if they have any complaints against them with their licensing body. In California, the SPCB will tell you the license status of both companies and inspectors.

Buying a Property with Wood Repairs

So you’re in escrow and the seller is fixing all the wood damaged discovered by their termite inspection. Great, right? Sorry, maybe not. I’ve discovered that it’s very common for sellers (intentionally or not) to cut corners on wood repair, as was the case with my house. I did not discover the shoddy work until it was too late, as most laymen wouldn’t. However this shoddy work can end up costing you down the road, as it is me.

So my advice is to get your own termite inspector (find one who is experienced in wood repair) do a follow-up inspection after the repairs are done and termite treatment complete. They will check that all the repairs were done, and at what quality they were done.


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