Ants Inside a New Home: Identification and Effective Baiting Strategies

Common Indoor Ants in New Construction

Small brown ants appearing along baseboards or sheetrock in a 3-year-old slab home are likely:

• Pavement ants (Tetramorium): Tiny, dark brown; nest under slabs; enter through cracks.
• Odorous house ants (Tapinoma): Small, dark; smell like coconut when crushed; multiple queens.
• Carpenter ants (Camponotus): Larger (1/4–1/2 in.), black or red-black; nest in wood; forage at night.

Why Sprays and Dusts Failed

Repellent sprays (defogger, boric acid dust) scatter colonies but don't eliminate the nest. Ants avoid treated areas and relocate. Terro (borax-based liquid bait) works only if ants accept it—some species prefer protein over sugar.

Effective Baiting Strategy

1. Identify food preference: Offer peanut butter (protein) and honey/sugar water (carb) on tape. See which they take.
2. Use matching bait:
   • Sugar feeders: Terro, Advion Ant Gel, or homemade borax-sugar syrup.
   • Protein feeders: Advance 375A, Maxforce Granular, or tuna-cat food mixed with borax.
3. Place baits near trails, not on them. Replace daily until feeding stops.
4. Do not spray near baits—contamination repels ants.

When to Call a Pro

• Carpenter ants (structural risk).
• Persistent infestation after 2 weeks of proper baiting.
• Ants in walls/voids inaccessible to baits.

Prevention

• Seal exterior cracks, utility penetrations.
• Trim vegetation away from foundation.
• Eliminate moisture sources (leaks, condensation).