How to Seal Siding to Keep Out Mice

By Chyrene Pendleton

They may look small and harmless, but mice can cause serious damage to your home and property. Mice also transmit pathogens that cause diseases. One common way mice enter your home is through irregularities in your home's foundation where it meets the siding. You can find gaps and cracks along the siding after inspection. Holes occur over time when seals crack around plumbing fixtures on your siding, allowing mice entrance into your home. By sealing gaps in your walls and siding, you can successfully secure your home from outdoor pests. Inexpensive and simple to do, sealing your siding only requires a little time to locate the cracks.

Mouse on swiss cheese
credit: NA/Photos.com/Getty Images

Step 1

Find the entrances mice use to enter your home. Crawl around the exterior of your home and use a flashlight to find cracks, holes and gaps in your siding.

Step 2

Look under the siding at the area meeting the foundation of your home for holes and gaps. Use a small mirror to help you see underneath areas.

Step 3

Slide a pencil into any hole or crack you find. If you can slide the pencil in, a little mouse can squeeze its body in.

Step 4

Go into your basement or attic with the lights off during the daytime. If you see sunlight streaming in, it may come through cracks in the siding. Spiders come through these cracks also, so look for their webs, which may point to cracks and holes.

Step 5

Put on your gloves, bring a rag for cleaning spills, then visit the cracks and gaps you spotted along your siding.

Step 6

Seal small cracks and gaps in your siding, under 1/4 inch wide, using an acrylic latex caulk. Simply apply this inexpensive filler into the cracks to seal. Paint works well over it.

Step 7

Seal larger gaps, up to 1/2 inch wide, with polyurethane caulk. This is messier than acrylic latex, but effective. Use mineral spirits and a rag to clean up any messes. Paint over it if desired.

Step 8

Fill gaps, large and small, with expanding foam--just spray it into the gap. Look for "minimal expanding" foam on the can's label for a cleaner job.

Step 9

Plug up larger gaps with pieces of copper scrubbing pad from the hardware store. Fill up the gap by spraying expanding foam into it. The copper keeps mice from eating through the foam later. Look for "minimal expanding" foam on the can's label for a cleaner job.