# One mouse in September is a kitchen in January.

> Rodent control in Calgary that starts at the envelope. 6 mm mouse gap, freeze-thaw joints, garage sleeves, docks. Exclusion first, bait second.

Canonical: https://www.frameworkpest.ca/pests/rodents/
Last updated: 2026-11-02

Mice & rats

Mice use freeze-thaw gaps. We inspect, treat what is already inside, and close the 6 mm joints so the problem does not move back in with the frost.

[Book this visit](https://www.frameworkpest.ca/contact/) [Get the season guide](https://www.frameworkpest.ca/guide/)

The organism, then the joint

Most ‘mouse problems’ in this climate are envelope problems. Mice move in late August and September as nights cool. They do not wait for snow. They use the joint that already takes water, the garage sleeve, the dock pit, the weep that was never baffled.

Penn State Extension notes a house mouse fits a hole about the size of a dime. Pest Control Technology documented mice passing that opening. What this visit costs is on [the ranges page](https://www.frameworkpest.ca/cost/), after we see the building.

## What we actually do

- Photograph and rank every opening that can take the species.
- Specify mesh, hardware, and sealant that survive Chinooks, not acrylic caulk.
- Remove the interior population with methods that match occupancy.
- Leave a file so the fifth November is not a sequel.

Biology here

- House mouse: roughly 6 mm. If a pencil fits, a mouse is considering it.
- Norway rat: roughly 12 mm. Slab joints, dock levellers, waste rooms.
- Calgary pressure rises before the first snow. Freeze-thaw reopens last year’s foam.

Assemblies we photograph

- Garage and man-door sweeps
- Pipe and cable sleeves at grade
- Parkade walls and elevator pits
- Dock levellers and seals
- Weeps, vents, and rain-screen cavities
- Waste rooms and boiler rooms

Questions

## About rodents

### Can you just bait the mice?

We can reduce a population. If the 6 mm joint stays open, you have bought a subscription. Bait without exclusion is how the same boiler room fails every fall.

### Is this safe around children and pets?

Placement and product follow Health Canada labels and occupancy. The permanent control is hardware, not a block in a corner a toddler can find.

| The hole | One mouse in September is a population in January if the gap stays open. Embarrassment in the kitchen is the internal problem. The gap is the job. |
|---|---|
| If we go | No droppings on the cutting board. Gaps on a list, then closed. You sleep. |