Flange in a Flash

Some doors and windows don't come with a built-in flange, the flat lip that normally gets sealed to a house's water-resistive barrier (WRB), the wrap that keeps water out of the wall behind the siding. Without that flange, installers have had to improvise a seal, often with mixed results. Typar has come out with a product meant to solve that: a double-sided tape called FlangeFlash that creates the flange on site.

One side of the tape sticks to the door or window before it goes in. Once the unit is set in place, the other side sticks to the WRB, tying the two together into one sealed, mechanically fastened flange. The tape uses the same adhesive formula on both sides, and the outer surface that faces the weather is rated to hold up to a year of sun exposure before it needs to be covered by siding or trim. The product was a finalist for a Most Innovative Building Material award at this year's International Builders' Show.

For a homeowner, this matters most if you're replacing windows or doors that don't have flanges, an approach used to fit certain openings or preserve existing trim. A tape like this is meant to give a tighter seal against air and water leaks, and better protection against pests getting in around the frame. FlangeFlash comes in 6-inch by 75-foot rolls for $125 and is sold wherever Typar products are available.