# Building-science glossary for pest exclusion

> Plain definitions of rim joist, sill plate, soffit, weep vent, freeze-thaw, the 6 mm gap and more, with links to the Calgary services that deal with each.

Canonical: https://www.frameworkpest.ca/glossary/
Last updated: 2026-10-25

Glossary

Calgary and area · Fully licensed and insured

Short answer

Twenty-one building terms that come up when we explain how pests get into Calgary homes, each in plain words with a link to the work that deals with it.

Air barrier · Vapour barrier · Rim joist · Sill plate · Soffit · Fascia · Flashing · Weep vent · Rain-screen · Penetration · Freeze-thaw cycle · Chinook · The 6 mm gap · Door sweep · Garage door bottom seal · Hardware cloth · Copper mesh · Harborage · Exclusion · Integrated pest management (IPM) · Crack injection

_Photo: Bailes, Penny Rogo, [Public domain](https://commons.wikimedia.org/wiki/File:Detail_view_of_north_front_roof_gable_decoration_of_1930_West_Laurel_Street,_facing_southeast._-_1930_West_Laurel_Street_(House),_Tampa,_Hillsborough_County,_FL_HABS_FL-483-9.tif), via Wikimedia Commons_

## Related reading

- [Exclusion engineering](https://www.frameworkpest.ca/services/exclusion-engineering/)
- [Structural assessment](https://www.frameworkpest.ca/services/structural-assessment/)
- [Building envelope pest science](https://www.frameworkpest.ca/insights/building-envelope-pest-science/)
- [Mouse-proofing](https://www.frameworkpest.ca/mouse-proofing/)
- [Framework Pest home](https://www.frameworkpest.ca/)

_Photo: Achim Hering, [CC BY 3.0](https://commons.wikimedia.org/wiki/File:Piping_floor_penetrations_nortown_casitas.jpg), via Wikimedia Commons_

## Questions

### What is a rim joist?

The framing board around the edge of a floor, sitting on the foundation. A common spot for gaps and penetrations.

### What is a weep vent?

Small openings at the base of brick or stone that let water out. They need screens that keep pests out without blocking drainage.

### How small a gap can a mouse use?

About 6 mm, according to Penn State Extension.

### What does freeze-thaw do to sealant?

Water freezing and thawing in a joint, which pushes it open over time. Calgary’s Chinook swings can take a wall through several freeze-thaw cycles in one winter, and each cycle works sealant and trim joints loose.

## Show us the gap.

Text a photo, call, or request a written quote.

[Request a written quote](https://www.frameworkpest.ca/contact/) [Call 825 747 5787](tel:+18257475787) [Text a photo](sms:+18257475787)