Home pest control
Perimeter pest control: a DIY guide
Stop bugs at the door. A treated band around your foundation keeps pests out before they get in.
The most effective way to keep ants, spiders, roaches, and other crawling pests out of your house isn’t chasing them once they’re inside, it’s stopping them at the perimeter. A treated barrier around the outside of your home creates a zone that pests cross to get in, and can’t survive. It’s the same approach professional pest control companies use on their regular service visits, and it’s very doable yourself with the right product and technique.
How perimeter treatment works
The idea is simple: apply a band of residual insecticide around the base of your home and the places pests use to get inside. Bugs that walk across the treated band pick up the product and die, so they never make it indoors. Because these products leave a residual, one application keeps working for weeks. The two areas that matter most are the foundation band (a strip of ground and wall around the base of the house) and the entry points, doors, windows, vents, pipe penetrations, and cracks where pests slip through.
Two products for the job
Bifenthrin Pro 7.9
7.9% Bifenthrin, the same active ingredient as Talstar and Bifen. A broad-spectrum insecticide with strong residual activity that controls 125+ pests, ants, spiders, roaches, ticks, millipedes, centipedes, scorpions, silverfish, earwigs, and more. Applied as a band around foundations and entry points.
Perimeter rate: 0.33 to 1 fl. oz. per 1,000 sq. ft.
Zone Plus
36.8% Permethrin, a broad-spectrum contact insecticide labeled for both indoor and perimeter use, controlling 100+ pests. A flexible option for treating the perimeter band plus indoor cracks and crevices.
Perimeter band 6–10 ft around the structure
How to apply a perimeter treatment
Mix in a pump sprayer. Dilute the product with water per the label rate for your target pest, fill the sprayer halfway, add product, then top off with water and shake to mix.
Treat the foundation band. Spray a band up the foundation wall (a couple of feet) and out onto the ground along the base of the house, a band several feet wide.
Hit the entry points. Treat around doors, windows, vents, utility and pipe penetrations, and any visible cracks, these are the highways pests use to get inside.
Let it dry. Keep kids and pets off treated areas until everything is dry. Apply in calm weather when no rain is expected for 24 hours so it doesn’t wash off.
Important safety notes
Both products are extremely toxic to fish and aquatic life, never let them run off into storm drains, ditches, gutters, or ponds, and don’t apply near water. Zone Plus contains permethrin, which is highly toxic to cats; never apply it where cats can contact wet treated surfaces, and keep all pets off until dry. Don’t reapply more often than the label allows (Bifenthrin Pro 7.9 is no more than once every 7 days). Always read and follow the full product label.
Make the treatment last: seal and clean up
A perimeter spray works better alongside a few simple habits that make your home less inviting to begin with: seal obvious cracks and gaps around the foundation and utility lines, keep mulch and dense vegetation from piling against the house, trim branches that touch the roof, and keep the area around the foundation free of leaf litter and debris where pests hide. The spray handles the pests that come anyway; these steps reduce how many come in the first place.
Common questions
How often should I do a perimeter treatment?
Most homeowners treat on a regular schedule through the warm months and reapply when they see renewed pest activity. Don’t reapply more often than the label allows, Bifenthrin Pro 7.9, for example, should not be reapplied more than once every 7 days. Heavy pest pressure or rain may call for retreatment within the labeled limits.
Where exactly should I spray?
Focus on a band along the foundation, up the wall a couple of feet and out onto the ground, plus all the entry points: around doors, windows, vents, pipe and utility penetrations, and visible cracks. Those are where crawling pests cross to get indoors, so that’s where the barrier does the most good.
Is perimeter spray safe around pets and kids?
Keep children and pets off treated areas until the spray has fully dried. Be especially careful with Zone Plus, which contains permethrin and is highly toxic to cats, don’t let cats contact wet treated surfaces. Once dry, treated areas are generally fine. Always follow the label’s specific precautions.
What pests does a perimeter treatment control?
A broad range of crawling and some flying pests, ants, spiders, cockroaches, ticks, millipedes, centipedes, scorpions, silverfish, earwigs, crickets, and more. Bifenthrin Pro 7.9 alone is labeled for 125+ pests, so a perimeter treatment handles most common household invaders in one pass.
Should I spray indoors too?
The perimeter band is the primary defense, but for an active indoor problem you can also treat indoor cracks and crevices where labeled, Zone Plus is labeled for indoor and perimeter use. For best results, treat inside and outside around the same time, and pair it with normal cleaning to remove what attracts pests.
Why do I still see bugs after spraying?
A few reasons: the barrier may have gaps (missed entry points), it may have washed off in rain, or there’s a strong attractant like standing water, food, or heavy mulch against the house. Re-check your coverage, seal obvious gaps, and remove attractants. Existing indoor pests also need to be dealt with separately from the outdoor barrier.
Ready to build your pest barrier?
Contact Agrisel to find a reseller carrying Bifenthrin Pro 7.9 and Zone Plus.