Why Don't My House Windows Drain When It Rains?

What Are House Window Drain Holes?

• If you look at the exterior frame of the windows in your house, you'll see small, square openings. These holes are known as "drain holes" or "weep holes." Their purpose is to allow water to drain out of the windows. They are designed to run rain water off the windows and away from the house. Otherwise, water will build up in the windowsill. It can spill over and run down the wall inside your house and cause damage.

Do the Drain Holes Let Air Into My House?

• Not at all. The manufacturers alleviated this possible problem when the windows were designed. There are small flaps that cover the drain holes. They open to allow the water to drain out, then close again. There is also a plexus of compartments inside the window frame. These chambers help make the frame more durable. They also prevent air from entering your house. Finally, the exterior holes and the interior drain holes don't line up, which helps obstruct the air.

What Causes the Drain Holes to Not Work Properly?

• If the windows are brand-new, there is a chance they weren't installed properly. If they were installed upside down, for example, the drain holes can't work like they were designed to. The drain holes may have been plugged shut with caulking or debris from building materials. Dirt, dead bugs, leaves and other debris easily can collect in the window frames and clog them as well.

Regular Maintenance Needed On the Drain Holes

• Every year before the rainy season begins in your area, inspect the drain holes. If the windows have screens, they need to be removed first. Make sure the holes are clean and the sill is free from obstructions. Use a soft-bristled broom or a vacuum to clean the windowsills. Use a small, soft bottle brush to clean the drain hole openings if needed. Clean them gently so you don't damage the small flaps.