CHAPTER 10: TECHNICAL CRITERIA
If greater than maximum allowable noise levels exist, then acoustical
Preservation Officer, and the Advisory Council on Historic Preservation.
treatment is required. Under these circumstances, the following is
This coordination must start early in the planning process to allow for
recommended:
appropriate reviews.
All window and door glazing in this area is to be acoustically laminated
Any GSA undertaking significantly affecting any building included or eligible
glass with an STC rating of 35 to 45, having an air space of 50 mm to
for inclusion on the NRHP will have to be evaluated in accordance with
100 mm. (Conventional double glazing and thermal glazing is not ef-
Section 106 of the Historic Preservation Act of 1966, as amended. Work
fective in this case.)
on historic buildings, structures, or properties should comply with the
Exterior doors in these spaces are to be high-quality commercial doors
Secretary of the Interior's Standards for Rehabilitation and Guidelines for
with an STC rating of 30.
Rehabilitating Historic Structures (current publication) and the Fire Safety
Sound-rated doors are an acceptable but more costly solution.
Retrofitting in Historic Buildings (August 1989), jointly written by the Advisory
Council on Historic Preservation and the General Services Administration.
10.6.2 Modulating Interior Noise Generated Within the Space:
In addition to standard commercial construction, other means should be
considered to ensure sound control within the center:
Acoustical material at the ceiling.
Three categories of acoustical concerns are: (1) controlling exterior noise
Cork, linoleum, or carpet, (either through the use of non-slip throw rugs
entering the space; (2) modulating and controlling the transfer of interior
or permanently installed), should be provided in appropriate spaces.
noise generated within the space; and (3) controlling the transfer of noise
Carpet may be particularly effective in corridors which can be particu-
between tenants adjacent to the center.
larly noisy due to the narrow configuration.
10.6.1 Control of Exterior Noise:
Sound attenuating wall finish should be provided where appropriate.
Minimizing exterior noise is typically required only when the center is
Baffles, banners, and fabrics should be considered in the design to help
adjacent to or near airport flight paths, major highways, or busy rail lines.
absorb the high level of sound generated within a center.
The RCCC must approve use of sites exposed to high noise levels. If
proximity to high levels of noise is unavoidable, acoustical mutigation
10.6.3 Controlling the Transfer of Noise Within Space:
measures are necessary. Maximum acceptable noise levels are dependent
Maintaining low noise levels in sleeping/napping and quiet areas is
upon which area of the center is subjected to the noise and whether the
important. There are various ways of achieving this to include the following
sound is continuous or intermittent. Maximum acceptable noise levels at
methods:
the center's exterior are as follows:
Extend interior partitions to the structure above the ceiling.
Partitions may be single layer wall board but should have cavity insula-
Outdoor play yards
tion and should be completely caulked at the top and bottom of the
Continuous: 70 dBA (decibels)
partition.
Intermittent: 80 dBA
Doors opening onto noisy areas should be solid core.
Use fabrics and baffles to absorb sound.
Centers with sleeping and quiet areas placed next to outside wall
Provide acoustical baffles in all duct work which penetrates sound at-
Continuous: 60 dBA
tenuating partitions.
Intermittent: 65 dBA
Avoid back-to-back electrical outlet boxes.
10.6.4 Controlling the Transfer of Sound to Adjoining Spaces Outside
Centers with sleeping and quiet areas protected and not located along
Center:
outside walls
Separation between child care centers and adjacent office space is
Continuous: 65 dBA
recommended to be STC (sound transmission coefficient) 55. Note that
Intermittent: 70 dBA
this will involve a considerable expense since partitions need to be not only
PBS-140 - July 2003
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