Exterior Soundproofing That Works - Continued
Normal wood-frame construction — 1/2-inch drywall, 3
1/2-inch studs and insulated cavity, and 5/8-inch sheathing
with siding — does not create a noise path that requires
treatment. However, uninsulated wall and ceiling framing may
require treatment. A ceiling that is part of the roof assembly
is exposed to more outside noise energy than a flat ceiling
under an attic space. To absorb some of this energy, we
increase the surface mass by applying an additional layer of
5/8-inch blue-board with a plaster skim coat, going directly
over the existing layer of gypsum (Figure 7). Where attics
exist above ceilings, no acoustical treatments are generally
required as long as the ceiling has at least one layer of
1/2-inch gypsum board, and there is at least 9 inches of
insulation in the joist bays.
7. Applying the principle that surface mass
absorbs noise energy, adding an extra 5/8-inch-thick
layer of gypsum blueboard with a plaster skim coat
helps to reduce the noise transmitted through flat-roof
and cathedral-style ceilings.
Quiet room. Boston's Logan
Airport program offers participating homeowners an extra
measure of sound insulation beyond the typical door and window
treatments. Homeowners may choose one room in their home to
receive a "quiet room" treatment that effectively creates a
room within the existing room. Any wall or ceiling in the
designated room that has exterior noise exposure will have a
second wall or ceiling constructed 1 inch inside of the
existing surfaces (Figure 8). This, of course, results in some
downsizing of the room's dimensions.
8. Double wall and ceiling construction
decouples, or isolates, the interior space from the
exterior building envelope. Although the existing room
size is slightly reduced, the thunder of a passing jet
is lowered to background noise.
Decoupling these rooms works very well — the thunder of a
jet departing is reduced to background noise. The average
tested noise rating of a quiet room is 45 dB — a 10 dB,
or 50%, noise reduction beyond that achieved by our normal door
and window treatments.
For these rooms to be optimally efficient, careful attention
to detail is a must. We make sure that no elements bridge the
gap between the new and existing walls and/or ceilings, and
that seams and holes are tightly sealed. These are the
• Set the new wall plate in acoustical sealant where it
is in contact with the floor.
• Seal all electrical wall switches and receptacles with
the same sealant.
• Use the standard elements of a normal 2x4 wood-framed
wall in the double-wall construction, and include R-11
insulation (Figure 9).
9. Double-wall 2x4 framing set in acoustical
sealant caps the top and bottom of an existing
boxed-out lower wall section. Fiberglass batt
insulation absorbs sound energy. Resilient channel
crosses 1x3 strapping over the existing ceiling, which
is covered with semi-rigid acoustical fiberglass
insulation, followed by a layer of 5/8-inch-thick
blueboard with a plaster skim coat.
• Replace any windows in the existing wall with a new
• The double wall also receives an acoustical window,
creating a double window construction (Figure 10).
10. Even the windows get doubled in a
sound-insulated room. Thermopane glass, minimum 2-inch
air spaces between units, and a high-performance storm
window present an effective barrier to external
• To decouple the ceiling, install 3/4-inch-thick
acoustical fiberglass insulation between wood strapping,
directly over the existing ceiling.
• To reduce the transmission of vibration, cross the
wood strapping with RC-1 resilient channel, and fasten a layer
of 5/8-inch blueboard to it.
• A layer of skim-coat plaster and a prime coat of paint
finish the job.
The only thing left for the homeowner to do is the final
painting and decorating.
One of the main goals of the residential insulation programs
is homeowner satisfaction and community goodwill toward the
airports. As a testament to the adaptability of people, not to
mention their savvy in not passing up a good deal, one program
participant, when asked if she noticed the difference after her
home was sound-insulated, responded, "I've lived here for 32
years, so I don't even think about the noise anymore, but I'm
happy with the job —it looks very nice."
AIA, is a principal and architect at the Jones Payne
Group in Boston, Mass.
889 Valley Park Dr.
Shakopee, MN 55379
http://www.chemrex.comSonneborn's Sonoclastic NP1
Sonneborn's Sonolastic Omniseal
1551 Mount Rose Ave.
York, PA 17403
http://www.grahamarch.comAluminum acoustical windows
1400 Main St.
Waltham, MA 02451
http://www.harveyind.comVinyl acoustical windows
P.O. Box 127
Quincy, PA 17247
http://www.armaclad.comArmaclad storm doors
J.B. Sash and Door
280 Second St.
Chelsea, MA 02150
http://www.jbsash.comWood replacement windows
Primary solid-core wood doors
1323 S. 11th Ave.
Wausau, WI 54401
http://www.kolbe-kolbe.comWood replacement windows
4041 N. Santa Fe
Oklahoma City, OK 73118
http://www.mdteam.comFlex-O-Matic door sweepMarvin
P.O. Box 100
Warroad, MN 56768
http://www.marvin.comWood replacement windows
P.O. Box 112
Northumberland, PA 17857
http://www.mohawkdoors.comPrimary solid-core wood doors
801 Boon Ave. North
Minneapolis, MN 55427
http://www.monray.comAluminum acoustical windows
Patio storm doors
228 W. 6th Ave.
Oshkosh, WI 54902
http://www.doors-windows.comPrimary solid-core wood
165 Wambold Rd.
Harleysville, PA 19438
http://www.pecora.comDynatrol I, 864, and 863
P.O. Box 2469
Shawnee Mission, KS 66201
http://www.peerlessproducts.comAluminum acoustical windows
Sliding storm doors
P.O. Box 484
Elmer, NJ 08318
http://www.premiersealants.comTremco's Dymonic sealantRepublic Windows
930 W. Evergreen Ave.
Chicago, IL 60622
http://www.republicwdws.comVinyl acoustical windows
Visco Weather Seal
166 Valley St., Bldg. 7
Providence, RI 02909
Uni-Check door sweep
One Weather Shield Plaza
Medford, WI 54451
http://www.weathershield.comWood replacement windows