How to Block Pests From Weep Holes

Block brick weep holes with copper mesh pushed just inside the opening. It stops insects, scorpions and mice while still allowing the wall cavity to drain and breathe. Never seal weep holes with caulk or expanding foam, which traps moisture and creates a far more expensive problem.

What weep holes are for

Brick is not waterproof. Water passes through it and runs down the inside face, and weep holes let that water escape at the bottom course. They also ventilate the cavity. Both functions matter, which is why the goal is a barrier that breathes rather than a plug.

Why copper and not steel wool

Steel wool works mechanically and then rusts, staining the brick with orange streaks that are difficult to remove. Copper mesh does not corrode in the same way and holds its shape. It costs a little more and it looks the same in five years.

The method

• Cut the mesh into strips roughly three or four inches long
• Roll each strip loosely rather than compressing it into a plug
• Push it into the weep hole with a screwdriver so it sits just inside the face of the brick
• Leave it snug but not packed tight, so water can still pass
• Work along the entire bottom course, including the back of the house and behind shrubs

What it will and will not stop

It reliably stops scorpions, most crawling insects and mice. It will not stop something that can climb and fly to an upper opening, which is why eaves and screens matter too. On its own it is still one of the highest-value hours you can spend on a brick home.

See our perimeter pest control program