Pittsburgh Brick and Hillside Homes: Where Rodents Get In
Pittsburgh's housing stock is older than most American cities' and sits on hills. Stone foundations, shared walls and sloped lots create specific rodent routes that this guide walks through.
Stone and brick foundations
Fieldstone and old brick foundations often have soft mortar, small gaps at the sill and openings where utility lines were added later. Rats need about half an inch and mice about a quarter inch.
- Look for crumbling mortar and gaps at the base of the wall.
- Check where gas, water, cable and electric lines enter.
- Inspect old coal chutes and cellar windows.
Hillside lots and retaining walls
Soil slopes and retaining walls give rats ready burrow sites right beside the house. Burrow holes are usually two to four inches wide with smooth edges.
Walk the uphill side of the foundation and the base of every retaining wall once a season.
Shared walls and rowhouses
In attached homes, rodents can move between units through shared wall cavities and basements. A sealed unit next to an open one will stay under pressure.
If you share walls, tell your neighbors and landlord early, since a one house fix rarely lasts.
Porches, garages and outbuildings
Old porches, detached garages and sheds are common nesting spots. Rodents may use them first and then move into the main house.
- Keep stored items off the floor.
- Replace worn door sweeps and garage seals.
- Trim back shrubs touching the walls.
What to seal with
Use materials rodents cannot chew through, such as steel mesh, hardware cloth, metal flashing and cement based patching products. Foam and plastic alone will not hold.
Frequently Asked Questions
Why do older Pittsburgh houses get more rodents?
They tend to have stone foundations, cracked mortar and more places where utilities enter, which creates more openings.
Is it worth sealing a rowhouse if my neighbor has mice?
Yes. Sealing your side makes it harder for them to enter your unit, though shared walls mean a coordinated fix works best.
What is the best time to seal my home?
Late summer and early fall, before the first cold nights push mice indoors.
Sources
Rules and numbers on this page come from these public sources. Check them for the latest wording, since agencies update their pages.