Recording - September 2013 - 44

Figure 5. These gaskets go under the decorative
plate. They’re intended to help save energy by
blocking drafts, but they’ll also help block sound
from leaking through the wall.

Figure 6. Self-adhesive weatherproofing tape
works wonders for acoustic sealing of doorways.

weatherproof your home. Nice that it
works out that way! You’ll want it
thick enough to fill the gap, but not
so much that it’s difficult to close and
latch the door. Install it so that the
closing door compresses it against
the jamb, rather than on the door
frame where the door would wipe
across it (as shown in Figure 7—picture A on the left is correct, pictures
B/C at center/right are incorrect).
This will help the gasket last longer.
Be very careful not to leave any
gaps—these will compromise your
efforts to stop sound leakage.
For door bottoms, there are a
number of products, from thresholds with integral seals to automatic
drop seals that drop to the floor
when the door is closed. Visit
www.kncrowder.com and look over
their weather stripping, threshold,
and auto door bottom sections for
lots of ideas. Consider using a sealing threshold with an auto drop seal
to ensure an airtight seal. If you use
a threshold with your door, be sure
to also apply acoustic sealant underneath it to ensure it is airtight.

Don’t let the door hit you on the
way out
Big sound leakage culprits are
doors and windows. Hollow-core
doors and single-pane windows
(common in some homes and
offices) are only marginally better at blocking sound than hanging a piece of cloth over the
opening to the room. There’s a lot
of room for improvement.
For doors, the best bet is, of
course, a sound rated door. But
switching to a solid core door
that mates flat against the door
jamb will help a lot, and it costs
a lot less.
Next, use an acoustical sealant
to seal the entire joint between
the door frame and the jamb; any
incomplete sealing here will compromise your efforts. Be sure to
apply the sealant on the side
opposite from where the door
mates with the door jamb. This
will make sure it doesn’t interfere
with the door closing, and will
allow the installation of gasketing
where the door meets the jamb,
which is the next step.
Now install self-adhesive, closed
cell weatherproofing tape (Figure
6) on the door jamb where the
door meets it. That’s right—the
same stuff you have around to

I see the light!
The next item on the sound leakage agenda is the windows. Your
first task is to assess the window
quality. If they are older singlepane windows, seriously consider
replacing them with vinyl-framed
dual-pane ones. The vinyl frames
seal tightly and the dual panes significantly reduce the sound transmission through the window. You’ll
also significantly improve your
energy efficiency, by the way.
Another method to seal a window is to build a cover that fits
tightly in the window. First install
two strips of the same closed cell
foam you used on the door around
the inside of the window frame;
one strip closer to the outside, and

Figure 7. Install gasketing so that it’s compressed by the door when you close it (A). Don’t put it along the edge where the striker
plate goes (B and C); it may seal tightly at first, but as you use the door, friction will cause it to eventually get torn loose.
44

RECORDING September 2013

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Recording - September 2013

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