Universal vent cap solves kitchen leak

Q: Every time it rains hard and with wind blowing from a certain direction, water comes down my kitchen range hood’s ventilation pipe. Usually the water is contained to the two plastic drawers at the back of the hood. But during a recent storm, water dripped from one of the two fans.

This has been a problem ever since the new hood and pipe were installed. I know the problem comes from the cover on the end of the vent pipe–the 6-inch-long piece of sheet metal attached to the end of the pipe above the roof–being too short. I thought of a bigger cover but found what I currently have is the standard; there is no other design.

Is there any way to fix this? My range hood was damaged from a storm. The openings of the pipe cover face southeast and northwest.

A: From what you describe, the cap on your vent pipe looks like a “T,” with the openings facing northwest and southeast. Although we’ve seen lots of these, we also have seen at least two others styles of vent cap.

We were puzzled by your remark that you had the standard and there is no other design, so we did a little detective work. Kevin looked out his bathroom window to check out the shape of the range hood vent on his house. The bathroom overlooks the single-story garage that is home to this vent. Believe it or not the vent is essentially flat. It looks like Han Solo’s ship–the Millennium Falcon–from “Star Wars.” The outlet is covered by a concave piece of sheet metal that prevents water penetration. An air gap of about 1 inch allows cooking vapor to escape. The 5-inch pipe attached to the vent penetrates the roof and the range hood pipe attaches in the attic.

Thinking that this is probably not your situation–your vent pipe penetrates the roof to the outside–we checked the local home improvement store and found a product called a universal vent cap. It comes in 3-, 4- and 5-inch sizes and costs about $10.

One of these sizes should fit your vent. The caps are round with protection around the top and sides to prevent water penetration. As with the “Star Wars” vent on Kevin’s house, cooking vapors escape through an air gap at the top of the cap. We suggest that after you determine the size of the vent pipe, you replace the “Model T.”

Bill and Kevin Burnett will attempt to answer your questions, although the volume of e-mail sometimes makes this impossible. Contact them at sweat-equity@comcast.net.