How to Prevent Termites: A Homeowner's Guide

No home is fully termite-proof, but you can make yours a much harder target. Controlling moisture, breaking wood-to-soil contact, sealing entry points and getting periodic inspections removes most of what draws termites in.

Moisture and accessible wood, mostly. Leaks, poor drainage, wood-to-soil contact, firewood against the house, and bare or damaged wood all make a home more attractive — subterranean termites especially follow moisture.

Mulch itself is poor food for termites; the University of Kentucky says they are drawn to it mainly because it holds moisture and insulates the soil, and piling it against the foundation also bridges soil to siding. Use it sparingly, a couple of inches deep, and never let it touch wood siding or door and window framing, which should sit at least 6 inches above the soil.

Older SGV homes need the basics plus vigilance: fix moisture, separate wood from soil, seal and repair weathered wood, and get a WDO inspection every two or three years if the house has exposed eaves and trim. That is more often than the University of California's general guidance of every 3 to 5 years, because an older home's age and original wood make early detection especially valuable.

Yes — that's exactly when prevention pays off. Termites work unseen for years, so periodic inspections catch a new problem while it's small and localized, long before it becomes costly structural damage.

For subterranean termites, yes: a professional soil-applied termiticide barrier, or in-ground bait stations around the house that intercept foraging termites before they reach the framing and are serviced yearly; we use bait stations. For drywood termites, dozens of preventive products are registered, but the University of California notes there are no field studies of how they perform against California drywood termites, so there are no guidelines for using them yet. Paint and screens can act as barriers, though UC notes they degrade and can be breached, which is why a regular inspection is the practical prevention.

It depends on what the house needs: a bait-station ring is priced by the number of stations and the yearly service, and an annual inspection is a single scheduled visit. We quote it in writing after looking at the house, and the walk-through is free.

Not completely. The University of Kentucky notes termites can still enter pressure-treated wood through cracks and cut ends or build tunnels over its surface, and the University of California warns subterranean termites can build shelter tubes over treated wood to reach untreated wood above it. Treated or naturally resistant lumber helps where wood must touch soil, but it does not replace clearance, moisture control and inspections.

Swarms are seasonal, but subterranean termites can forage year-round in California, according to the University of California. Foraging is minimal from November to February, moderate in spring and fall, and high but erratic in summer, when even a little rain brings more foragers up. That is why prevention and inspections are a year-round job, not just a spring one.

Not reliably. The University of California says there are no reliable over-the-counter termite control products for the public in California, all effective products are for professional use only, and the products needed to control drywood termites are not sold to homeowners. What a homeowner can do well is the non-chemical side: moisture control, wood-to-soil clearance, removing wood debris and regular inspections.