When my insulated concrete form (ICF) house was bricked on the outside, the masons put weep holes every few feet. I know weep holes are needed in wood frame construction, but I’m not sure if they’re necessary on an ICF house. Can I fill in the weep holes, since they attract insects like dirt dauber and wasps? -John

Hi John,

Insulated concrete form (ICF) construction consists of hollow, foam blocks that are stacked to form walls, then filled with concrete to make a structure that is both durable and well insulated. The exterior walls of ICF construction are then covered with brick, stucco, or siding.

Even though the ICF wall is behind the brick veneer, you should still keep the weep holes in the brick open, since moisture can enter the gap between the two walls from condensation, leaks, or driving rain.

Instead of closing the weep holes, try stuffing black fiberglass screening into the holes. The screen will keep the insects out but still allow any moisture to pass through.

Good luck with your project,

Further Information

• Increase Energy Efficiency in Your Home with Insulation (video)
• Vapor Barriers in Your Home (article)
• How to Deal with Wasps (article)

Tags: , brick, concrete, ICF, moisture, vapor barrier