We had more than 10 years of a highly competitive "seller's market" where the seller could dictate the terms of the contract of sale to a hapless buyer. The worm has turned in many local markets (with the exception of Palo Alto, Menlo Park and Los Altos) and buyers have more clout in negotiations. The Pest Control section of contracts once routinely crossed out by most agents is now showing up in more contracts than it has for years.
What are termites and should you be concerned? Termites are common and some evidence of termite activity is routinely found during pest-control inspection on the Peninsula and throughout California.
Subterranean termites are by far the greatest risk for doing serious damage to structures in a relatively short period of time. These termites live in the earth 24-7 and are pervasive in our area. They do not fly around. When they feast on wood they do so by building a mud tube from the ground onto the wood they want to eat. Without earth-to-wood contact they die.
In other words if you break the tube coming out of the earth then those on the wood side will die and those on the earth side will either have to rebuild the mud tube or retreat to the earth until another day. Thus, if you could find all the tubes you could effectively kill all of the termites eating your structure just by breaking down the mud tubes.
Pest-control contractors will generally knock down the tubes and then inject pesticides in the soil in the area where the termites are tubing up. It would be rare that they would suggest trenching around an entire structure unless the subterranean termites were tubing up everywhere. Using vast amount of poison everywhere is obviously unnecessary and unprofessional.
The pesticides used today tend to break down in the soil over a fairly brief period of time versus the DDT-type pesticides that take 50 years or more to break down. Such pesticides are not legal to use. If you have any old pesticides with DDT they should be disposed of at the hazardous waste center that the City of Palo Alto runs for residents every month. (Upcoming events are Saturdays, May 7 and June 4, 9 a.m. to noon, at 2501 Embarcadero Road, Palo Alto.)
Drywood ("flying") termites can cause damage to structures, but generally they take many years to do serious damage. When the inspector can isolate the area and access the area where the termites are, they can be locally treated with a small quantity of pesticide or maybe some other more bio-friendly insect-killing substance.
I once tried the "microwave" method and the contractor nearly burned down the structure and termites were not eradicated. I will not try that again.
If they are found in an isolated and accessible area then local treatment is possible. If there is scattered evidence (wings, droppings, etc.) in different areas of the structure OR in areas that are not accessible, then the only practical method is tenting using Vikane gas. If you decide not to tent then over the long term these insects might do serious damage.
However, sometimes the termites fly in, create a family and then mysteriously leave doing little or no serious damage. Tenting is not a deterrent to drywood termites that may fly in the day after the tenting is done and start a new family in your nice tasty wood house. Remember, drywood termites generally take a long time to reproduce and cause a lot of damage versus the subterranean termites that have thousands or millions of friends living in the earth below your house ready to have a feast once some nice wood is found. Most pest-control contractors do not recommend tenting more than once every five to 10 years.
The problem with all termite infestations is that more often than not, the damage is hidden in areas that cannot be viewed or are inaccessible, hence the need to open up areas where there is a lot of activity to verify that the integrity of the structure is in good condition. A minor amount of damage often does not require wood replacement, however on a property that I manage we recently discovered that subterranean termites had hollowed out a supporting beam. The damage was difficult to see until you touched the beam and realize that it was basically paint and little or no wood left!
Signs of termites can often be subtle, so getting an inspection every three years is a great idea.
Termites are attracted to water, so wet wood caused by leaking roofs, leaking sewer lines, leaking shower pans and the like often serve as the appetizer for the main meal. That's another reason to make sure that these problems are dealt with so that termites are not attracted to your house. Any earth-wood contact is an easy highway for subterranean termites. That's why fences don't last and why you don't want earth-wood contact under or around your home. Grading dirt so that it is below all wood surfaces and sloping away from your foundation is always a good idea.
The skill of the pest-control contractor is in his or her ability to observe all of the areas of your home where termites might be. If you have a lot of personal property in the way, this hinders the inspection. Or if your inspector cannot get under your house because he or she is too big, then you will never know if you have a problem.
One last hint: Make sure that the contractor removes ALL evidence of the termite infestation (whether drywood or subterranean). If they fail to do this it may look like you have an infestation to the next inspector as they do not carbon-date evidence of insect activity and often there is no easy way to tell if the damage is new or ancient.
Lastly, any time a pest-control contractor replaces wood in your home as a result of an inspection, a building permit with the City is required. You can have your own general contractor do the wood-replacement/repairs (often a good idea) instead of using the pest-control contractor, and have the pest-control company do only the chemical treatment.