# Crawl Space Rodent Proofing: Sealing Them Out > How rodents get into a crawl space, how to seal the entry points properly, and why cleanup without exclusion just gives them a cleaner space. URL: https://910crawlspacepros.com/guide/crawl-space-rodent-proofing/ Home / Crawl Space Cleanup / # Crawl Space Rodent Proofing What to do now Crawl Space Rodent Proofing Exclusion first. Everything else is temporary. Updated 2 August 2026 Rodents enter a crawl space through foundation vents, gaps around pipe and cable penetrations, and unsecured access doors. Sealing those with steel mesh or hardware cloth is the permanent fix. Cleanup without exclusion simply provides a cleaner space for the next arrivals. ## Where they actually get in Damaged or missing vent screens are the most common route. After that, the gaps around plumbing and electrical penetrations through the foundation wall, which are frequently left unsealed by the original trades. An unsecured or ill-fitting access door is the third. A mouse needs a gap the width of a pencil; a rat needs about an inch. ## What to seal with Steel wool or hardware cloth at penetrations, backed with sealant. Not expanding foam alone — rodents chew straight through it, and foam-only repairs are the most common thing we find already failed. Vent screens should be metal mesh rather than plastic, and the access door needs a frame it actually seals against. ## Why the contamination matters Droppings and nesting material are not ordinary debris. Disturbing them dry aerosolises whatever they contain, which is why removal is done with respiratory protection and the material is wetted rather than swept. That handling is the difference between a cleanup and a health exposure, and it is worth asking any contractor how they intend to do it. ## The bottom line Seal the entries first, then clean, then treat. Doing it in the other order means doing it again. For a number against your own crawl space, use the cost estimator , or call (910) 886-2018 and we will come and measure it. Get an exact quote A free on-site measure beats any online range. Website What do you need? Select a service… Crawl Space Encapsulation Crawl Space Insulation Crawl Space Waterproofing Crawl Space Mold Removal Crawl Space Vapor Barrier Installation Crawl Space Dehumidifier Installation Crawl Space Drainage Crawl Space Sump Pump Installation Crawl Space French Drain Crawl Space Cleanup Crawl Space Structural Repair Sagging Floor Repair Crawl Space Door Replacement Flood Vent Installation Not sure — I need someone to look ZIP code Continue Your name Phone What are you seeing? (optional) Back Request my inspection Got it — your request is in. We'll be in touch with a quote. Related service Crawl Space Cleanup Related guides Crawl Space Odor Removal Standing Water in Your Crawl Space: What to Do Signs of Mold in a Crawl Space All guides → , not a heading: this is a CTA, not a section of the document outline. --> Get your crawl space measured and priced Free on-site inspection across Wilmington and New Hanover, Brunswick and Pender counties. Free quotes within 24 hours. Call (910) 886-2018 Get a free quote ## Questions How much does crawl space rodent proofing cost? Typically $400–$1,200 for exclusion work depending on the number of penetrations and vents. Contaminated cleanup is quoted separately because the handling is different. Will encapsulation keep rodents out? It helps considerably, because sealing the vents and fitting a proper access door removes the main entry routes. But penetrations still need individually sealing. Is expanding foam enough to seal rodent entry? No. Rodents chew through foam readily. It needs steel wool or hardware cloth as the barrier, with foam or sealant only as a finish.