Termites, termite contracts and foundation soil: What homeowners should know

Termites cause expensive damage, and the problem often isn’t found until repairs are needed. Here’s what to watch for, what to look for in a termite contract and how to learn about the soil under your home. Many examples below come from Louisiana, where the LSU AgCenter studies termites closely.

Know your termites

Homes can face native subterranean termites and the invasive Formosan subterranean termite. The LSU AgCenter says Formosan termites have spread to 42 of Louisiana’s 64 parishes.

• In Louisiana, Formosan termites swarm from April to June, peaking in early to mid-May. They swarm at dusk and are attracted to lights.
• An older AgCenter article gives a slightly longer window: April to July, from dusk to midnight.

Signs of termites

According to the LSU AgCenter, look for:

• Discarded wings
• Mud tubes
• Water stains and moisture buildup
• Soft or hollow-sounding wood

The AgCenter’s current guidance recommends an annual termite inspection by a licensed professional. An older AgCenter article suggests every 3 to 5 years, so ask your pest control company what it recommends for your home.

Make your home less inviting

LSU AgCenter tips include:

• Turn off outdoor lights at night in May and June so they don’t attract swarmers.
• Remove wood, cardboard and other cellulose material from around and under the house.
• Keep mulch 8 to 12 inches away from the foundation.
• Fix plumbing and roof leaks, and make sure water drains away from the house.
• Don’t dig or disturb the soil within about a foot of the house. That’s where termite treatment is usually applied, according to the AgCenter.

Your termite contract: the Louisiana example

States license pest control companies and set rules for termite contracts. In Louisiana, pest control companies that do termite work must be licensed by the Louisiana Department of Agriculture and Forestry (LDAF). Companies also need an LDAF place of business permit. Under R.S. 3:3370:

• Termite work must be covered by a written standard contract.
• The contract must guarantee retreatment if termites come back within one year.
• The contract can be transferred to a new owner if you sell the house.
• The company must give you a copy of your contract within 30 days of a written request.

Read the contract before you sign. Check what it covers (retreatment only, or damage repair too), how often inspections happen and how renewal works.

What about soil and foundations?

You may have heard that clay soil is hard on foundations. The risk varies a lot from place to place, and even from lot to lot.

Local example: soil research for Caddo and Bossier parishes

A 2021 study in Frontiers in Built Environment assessed expansive-soil risk across Louisiana. It found the highest swelling potential in southeast and southwest Louisiana. It ranked East Feliciana as the least vulnerable parish, followed by six northern parishes that include Bossier and Caddo. The authors also note that all developed parts of the state have some risk. And because property values are high in cities, the study expects dollar losses from expansive soil to stay concentrated in a few places, including Shreveport.

Rankings like these are broad, so conditions can still vary from lot to lot. To learn about the soil under your home, look up your address in the free USDA Web Soil Survey. If you see cracks, sticking doors or sloping floors, have a qualified professional look before you pay for any repair.

Good drainage helps protect both your foundation and your home from termites. See our fall home checklist for gutter and downspout tips.