Ten years ago, caulks and sealants
were part of a home's exterior
weather barrier. Today, high-performance
sealants are also used inside
the house to keep conditioned air
from escaping. This column looks at
the best three sealants for residential
air sealing: siliconized acrylic latex,
silicone, and one-part polyurethane.
Quality Counts
Applying sealant is one of those
jobs where skimping on quality will
come back to haunt you later. The
reason is the high level of stress
found in most construction joints
and the ease with which they can
fail. A good sealant will stretch or
compress as much as 25% of the
original joint size. That exposes a 1/2-
inch-wide joint to potential failure
after a movement of only 1/8