Synopsis: Proper air-sealing is one of the keys to an energy-efficient house, but choosing the right air-sealing tape can be a challenge. In this article, senior editor Martin Holladay writes about his informal backyard test of 11 air-sealing tapes. Holladay attached several substrates to his shed, then applied strips of various tapes to see how they held up over the course of a late-fall month. The tapes use three types of adhesive: rubberized asphalt, butyl, or acrylic. The 11 tapes spanned a wide price range and included products from Dow, Venture, Nashua, Siga, Zip System, Polyken, 3M, and Pro Clima. The substrates included XPS, foil-faced polyiso, plywood, OSB, housewrap, and polyethylene. In the end, Holladay learned that there is no such thing as all-purpose tape and that certain tapes work better with specific substrates. This article includes sidebars about the economics of choosing tapes and substrates, and about the issue of vapor permeance.

Anyone building an energy-efficient house has to pay attention to air-tightness. Leaks can occur through cracks between panels of wall sheathing, around windows and doors, at wall and ceiling penetrations, and in a variety of other places. While some of these leaks can be sealed with caulk or spray foam, others are best sealed with a high-quality construction tape.

Manufacturers offer a variety of flexible flashings and construction tapes, ranging from inexpensive products that look like packing tape to European peel-and-stick tapes costing more than $100 a roll. Of course, virtually all manufacturers claim their products are sticky and durable. To sort the hype from the facts, I asked a number of builders about their favorite tapes, then tested 11 recommended products. While I still have questions, I gained a better understanding of how to use different tapes for air-sealing.

Three major types

Three types of adhesive are used to make…