Rodents: How Are They Getting In, How Do We Stop Them?

It’s critical that pest problems be identified and addressed as quickly as possible because rodents breed quickly — a single pair of rats can multiply into 640 within a year, and mice can multiply to over 1,000. Stopping them for good means finding the points of entry and sealing them up to prevent future invasion. Below are some of the most common entry points and exclusion solutions. Remember, when conducting your inspection, mice can fit through a gap of about 1/4 inch and rats through a gap of 3/8 inch.

Common Entry Points and Solutions:

  • Exterior doors — Damaged or worn out sweeps are one of the most common entry points. Most standard brush or vinyl sweeps keep out the weather but not mice and rats. All doors should be fitted with specialized rodent-proof door sweeps.
  • Vents and grilles — Protect them with screen or mesh and ensuring any voids or gaps around them are filled with a pest exclusion material.
  • Drain pipes — Rats are excellent swimmers. Make sure exterior drain and sewer access points are covered with an appropriate metal cover. Openings surrounding the drain should be patched or filled.
  • Vertical wires and pipes — Mice and rats are excellent climbers. Circular rat guards should be placed around all vertical wires and pipes.
  • Utility and other building penetrations — Check places where pipes, wires or HVAC enter the building and fill any gaps with pest exclusion material.

Ensure the exterior of the building, especially around the foundation, is free from harborage areas such as shrubs and ground cover, and eliminate any “bridges” to the roof, like overhanging trees.

This article originally appeared in the issue of .

About the Author

Drew McFadden is director of Marketing for Xcluder, and can be reached at [email protected].

Featured

  • Little Grand Market

    Designing for Belonging: Why Student Wellness Starts with Space

    From walkable site planning to flexible interiors, intentional design choices play a critical role in how students experience comfort, connection, and community.

  • Zurn Elkay Releases 2025 Sustainability Report

    Zurn Elkay Water Solutions recently announced the release of its annual sustainability report, according to a news release. The 2025 report discusses the organization’s efforts to maintain good environmental stewardship and the solutions provided in helping customers meet sustainability goals.

  • Miami University Approves New $242M Multipurpose Arena

    Miami University in Oxford, Ohio, recently announced that its Board of Trustees has approved construction of a new multipurpose arena at Cook Field, according to university news. The $242-million project will serve as a new centralized hub for student life and create space for economic development on campus.

  • Houston K–12 District Opens New Elementary School

    The Lamar Consolidated Independent School District (Lamar CISD) recently announced the completion of a new elementary school in a western suburb of Houston, Texas, according to a news release. Haygood Elementary School measures in at 110,000 square feet, has the capacity for 854 students, and is the first of three new schools scheduled to be built in the Cross Creek West community.