How to Pest-Proof Your Garage | PestControlBasics

📋 Steps

Seal the garage door bottom

Most garage door seals are rubber or vinyl that degrades or shifts. Install a new garage door threshold seal (glued to the floor) plus a bottom door seal. Together these eliminate the gap that allows mice, insects, and snakes entry.

Seal side and top door gaps

Inspect the sides and top of the closed garage door in daylight — any light visible means pest entry is possible. Replace or adjust weather stripping.

Seal all wall penetrations

Electrical conduit, gas lines, water pipes, and cable all penetrate garage walls. Seal around every penetration with copper mesh + caulk.

Address the entry door to the house

The door from garage to house interior is a second line of defense — it should seal completely. Add a door sweep and inspect the door frame perimeter.

Apply perimeter treatment inside

Apply bifenthrin spray to the garage floor perimeter and wall bases. Pest glue boards at corners provide ongoing monitoring.

💡 Tips

The most common garage pest pathway: mice enter through a gap under or beside the garage door, then enter the house through the interior door — addressing both stops the chain
Cars parked in garages bring in insects (especially Asian lady beetles and stink bugs) that have landed on warm surfaces — inspect your car during fall invasion season
Garage storage (especially cardboard boxes) provides excellent rodent and cockroach harborage — switch to sealed plastic storage bins

💰 Cost to Fix This Problem

Approach	Typical Cost	Best For
DIY materials only	$25–$75	Mild or early-stage infestations
Professional service (one-time)	$150–$400	Active infestations or when DIY has already failed
Ongoing service contract	$400–$800/yr	Prevention and long-term peace of mind

Approach

Typical Cost

Best For

DIY materials only

$25–$75

Mild or early-stage infestations

Professional service (one-time)

$150–$400

Active infestations or when DIY has already failed

Ongoing service contract

$400–$800/yr

Prevention and long-term peace of mind

Costs vary by region, property size, and severity. Get at least two quotes before hiring.

✅ How to Know It's Working

Pest control success is measured in weeks, not days. Here's what to look for:

Week 1–2: You may see increased activity as pests are flushed from hiding. This is normal.

Week 2–4: Activity should drop noticeably. Bait traps or sticky monitors should show declining counts.

Week 4–6: New activity near zero. Any resurgence means a population was missed or re-introduction occurred.

💡 Monitoring tip: Place sticky traps in corners and along walls before you start treatment. Counting catches weekly gives you objective data on whether the population is declining.

👷 When to Call a Professional

DIY is appropriate for small, contained infestations caught early. Call a licensed professional when:

You've tried DIY twice with no lasting improvement

The infestation involves a wall void, crawlspace, or area you can't safely access

There's a health risk involved (hantavirus, anaphylaxis risk, etc.)

The problem covers more than one room or a large outdoor area

You have children, elderly, or immunocompromised individuals in the household

⚠️ Rule of thumb: If you've spent more on DIY materials than a professional visit would cost, it's time to call.

❓ Frequently Asked Questions

How do I apply a perimeter spray correctly?

Spray the exterior foundation from ground level up 12-18 inches, plus 12-18 inches of ground outward. Also treat all entry points: door frames, window frames, and pipe penetrations. Use a pump sprayer with bifenthrin at label rate.

How often should I reapply?

Bifenthrin provides 60-90 days of residual protection. Heavy rain and sunlight degrade it faster. Most homes benefit from quarterly application in spring, summer, and fall.

Is perimeter spray safe for plants along the foundation?

Pyrethroids have low phytotoxicity but are highly toxic to bees. Avoid spraying flowering plants and apply in early morning or late evening when pollinators are inactive. Direct spray onto foundation and soil, not plant foliage.

Can I do perimeter spray myself?

Yes. Consumer-grade bifenthrin concentrate and a pump sprayer is all you need. The technique is straightforward. The main advantage of professional service is consistent scheduling and expertise identifying vulnerable entry points.