Dear Angie: Does spot treatment for drywood termites work? I have drywood termite damage to some interior trim and evidence of live termites (termite excrement, tiny sawdust pellets, and wings), is observed in one room of a large home, but in no other rooms. I'd prefer not to have to tent the entire home (and risk breaking tiles on the roof), but just spot treat if it's effective. Is it? – Martin K., Tampa, Fla.

Dear Martin: Spot treatments can be effective, but there are several factors needed for them to work. First, the termite problem needs to be isolated. There needs to be a clear sign of termite activity and the area needs to be easily accessible. Of course, it also won’t work if you aren’t using the proper product; specifically, a termiticide made specifically for spot treatments.  

Visual evidence and accessibility are critical to just how effective spot treatment will be. If you can inject the termiticide in the galleries – the “tunnels” termites form to travel inside wood – or on the termites, it should be effective. That, however, is the trouble with spot treating for termites. Because you can’t see inside wood or walls, you can’t be assured that the termites will come into contact with the treatment. There could also be several individual colonies inside the structure that you won’t be able to reach. If you don’t eradicate all the termites, they’ll continue to mate and multiply.

Tent fumigation is the only guaranteed remedy, because the fumigant penetrates all wood in the structure. Unfortunately, termite professionals often get called out to tent a structure after a homeowner has spent time and money trying spot treatments.

I recommend you have a thorough inspection done by a reputable, certified termite inspector. Check consumer reviews and look for information about your specific need to see how companies have performed. Get three estimates for the treatment and follow the advice of the company you decide to hire. If the problem is isolated, you might be fine with the spot treatment. If tenting the structure is needed, talk to the company and share your concerns about damage to the roof. Done carefully, there should little or no damage and the cost for any repairs should be minimal; especially when compared to the damage termites can do.

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