HomeMy WebLinkAboutCT 2018-0005; VILLAGE WALK; NOISE STUDY; 2018-04-17' #
NOISE STUDY
341 OAK AVENUE
CARLSBAD CA
Project Proponent:
TMS Oak Investments 8, LLC
29250 Paseo Sedano
San Juan Capistrano, CA 92675
Prepared by:
~6ltz tr:,;<l5MI
42428 Chisolm Trail
Murrieta, CA 92562
760-473-1253
April 17, 2018
Project: 1829-02 341 Oak Avenue Noise Report
APR 19 2018
CITY CF Ci ,:,, -0 , 7
PLANNING Gl'Ji ... '.i
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TABLE OF CONTENTS
TABLE OF CONTENTS .......................................................................................................................................... II
LIST OF FIGURES ••.•••••••••••••••.•....•....•......•••.•••••••••••••..••........••.•.•••••••••••....•....••...•.•••••••••...•....•....•..•••••••••••..•....•..•• II
LIST OF TABLES •••••••••.•••..••...••...•.•••••••••••••••••••..••...•...•...•••.••••••....•....•....••..•••••••••....•...•...••..•••••••••••..•...••.......••••••• II
APPENDICES ..•••••••••••••••••....•...••..••••••••••••••••••••••...••..•..•••••••••••••••••...•....•...••••••••••..•....•...•••••••••••••••..•...•...••.•••••••••. II
GLOSSARY OF TERMS •.•....•.....•...•••••••••••••••••.••....•...•••••••••••••••...••..•....•..•••••••••...........•••••••••••••...•...•..•••••••••••••••... Ill
EXECUTIVE SUMMARY •..••..••••••••••••••••.••••....•....•.•..•••••••••••..•....•..••...•••••••••...••....•.••••••••••••....•..••...•••••••••...••..•....• IV
1.0 PROJECT INTRODUCTION •••••••....•......••••••••••••••••••...•......•....•••••••••••......•••••••••••••••...•...•.•..•••••••••.•.•...•..••••••••• 1
1.1 PURPOSE OF THIS STUDY .................................................................................................................................. 1
1.2 PROJECT LOCATION ......................•.....•.....................•...•...•..................•......•......................•...•.................•...•... 1
1.3 PROJECT SETTING ...•............................•......•................................................•..•...•..........................•................. l
2.0 ACOUSTICAL FUNDAMENTALS •••••••••••••••••••.•....••.••••.•••••••••.•...••....••••••••••••...••...•...•••••••••••••••..•....•..••••••••••••• 4
3.0 SIGNIFICANCE THRESHOLDS AND STANDARDS •••••••.....•....•..•••••••••••••....•.•..••••••••••••••••..•....•.•••••••••••••.••...•..•. 6
4.0 NOISE ENVIRONMENT ••••.•••...••......•.••••••••••••••....•.....••••••••••••••••••....•....••••••••••••..•....•...•••••••••••.•....•...•...••••••• 8
4.1 EXISTING NOISE ENVIRONMENT ONSITE ...•......•••••••••• , ......................................................................................... 8
4.2 FUTURE NOISE PREDICTION METHODOLOGY .••......•..................•......•................•......•.....•.................................... 10
4.3 INTERIOR NOISE METHODOLOGY ......•......•.....................•.......•..•...............•......•...................•...•.....................•. 11
LIST OF FIGURES
FIGURE 1-1: PROJECT VICINITY MAP •••••••••••...•....•..•••••••••••..•••..••...•...••••••••••.••...••••••••••••..•....•..•••••••••••••.••..•...•••••• 2
FIGURE 1-2: PROJECT SITE PLAN ..••••••••••••••••.....•...••.••••••••••••..••...•..•••••••••••••.•....•••••••••••••••...•..•••••••••••.•••..•...••..•••• 3
FIGURE 4-1: AMBIENT MONITORING LOCATIONS .•••••••••••....•....••.•••••••••••••......•.••••••••••.••...••..••••••••••••.••..••.••.••••••• 9
LIST OF TABLES
TABLE 3-1: ALLOWABLE NOISE EXPOSURE1 ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 6
TABLE 4-1: MEASURED AMBIENT NOISE LEVELS .••••••••••••...•..••••••••••••....•....••••••••...••...•.••••••••...•....•.•••••••......•....•••• 8
TABLE 4-2: SOUND TRANSMISSION CLASS RATINGS ...•••••••••••...•...••••••••••.••...••••••••••.••...•...••••••••••...•...••••••••••••••..• 13
APPENDICES
INTERIOR NOISE MODEL CALCULATION .••...•.•..••••••••....•......••••••..•••....•....•••..••....•....••.•.•..••...•...••..•.•.....•.......•..••. 14
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GLOSSARY OF TERMS
Sound Pressure Level (SPL): a ratio of one sound pressure to a reference pressure (l..,er) of
20 µPa. Because of the dynamic range of the human ear, the ratio is calculated logarithmically
by 20 log (L/1..,er)
A-weighted Sound Pressure Level (dBA): Some frequencies of noise are more noticeable
than others. To compensate for this fact, different sound frequencies are weighted more.
Minimum Sound Level (Lm;n): Minimum SPL or the lowest SPL measured over the time
interval using the A-weighted network and slow time weighting.
Maximum Sound Level (Lmax): Maximum SPL or the highest SPL measured over the time
interval the A-weighted network and slow time weighting.
Equivalent sound level (L.,q): the true equivalent sound level measured over the run time.
Leq is the A-weighted steady sound level that contains the same total acoustical energy as the
actual fluctuating sound level.
Day Night Sound Level (LDN): Representing the Day/Night sound level, this measurement is
a 24 -hour average sound level where 10 dB is added to all the readings that occur between 10
pm and 7 am. This is primarily used in community noise regulations where there is a 10 dB
"Penalty" for night time noise. Typically LDN's are measured using A weighting.
Community Noise Exposure Level (CNEL): The accumulated exposure to sound measured
in a 24-hour sampling interval and artificially boosted during certain hours. For CNEL, samples
taken between 7 pm and 10 pm are boosted by 5 dB; samples taken between 10 pm and 7 am
are boosted by 10 dB.
Octave Band: An octave band is defined as a frequency band whose upper band-edge
frequency is twice the lower band frequency.
Third-Octave Band: A third-octave band is defined as a frequency band whose upper band-
edge frequency is 1.26 times the lower band frequency.
Response Time (F,S,I): The response time is a standardized exponential time weighting of
the input signal according to fast (F), slow (S) or impulse (I) time response relationships. Time
response can be described with a time constant. The time constants for fast, slow and impulse
responses are 1.0 seconds, 0.125 seconds and 0.35 milliseconds, respectively.
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EXECUTIVE SUMMARY
This noise study has been completed to determine the noise impacts associated with
the development of the proposed residential project. The project known as "341 Oak
Avenue" consists of eight (8) new multi-family townhome units. The project site is
located at 341 Oak Avenue between Lincoln Street and Washington Street, west of
Interstate 5 in the City of Carlsbad CA. Access to the project site would be taken from
Carlsbad Village Drive to the north and Carlsbad Boulevard to the west.
The results of this analysis indicate that background noise from Carlsbad Village Drive and
Carlsbad Boulevard, and train activities from nearby SDNR are the principal source of
community noise that will impact the site. Due to the distance of the roadways and train
activities to the project site as well as shielding from existing and proposed structures,
noise levels at the private outdoor use areas were determined to be below the City of
Carlsbad normally acceptable goal of 60 dBA CNEL.
Additionally, the edge of the project is near the unshielded 60 dBA CNEL contour of the
railway and full disclosers should be posted and given to potential tenants or buyers
according to the City of Carlsbad Noise Guidelines Manual Land Use Section C.5 as
stated: Enforce the policy of the City that 60 dBA CNEL is the exterior noise level to
which all residential units should be mitigated. Additional disclosure actions (easements,
deed restrictions, recorded notice, etc.) may be required of developers/sellers of noise
impacted residential units.
The City of Carlsbad as part of its noise guidelines also states, consistent with Title 24 of
the California Code of Regulations (CCR), a project is required to perform an interior
assessment on the portions of a project site where building fa~ade noise levels are above
60 dBA CNEL in order to ensure a 45 dBA CNEL interior noise level. Thus, it is
recommended that interior noise reduction methods (i.e., dual-paned glass treatments)
having a sound transmission classification {STC) rating of 26 or higher be installed to
remediate these instantaneous noise levels.
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Ldn Consulting, Inc. 4/17 /18 1829-02 341 Oak Avenue Noise Report
1.0 Project Introduction
1.1 Purpose of this Study
The purpose of this Noise study is to determine potential onsite traffic and train noise
impacts (if any) created from Carlsbad Village Drive, Carlsbad Boulevard and the San
Diego Northern Railway (SDNR). Should impacts be determined, the intent of this study
would be to recommend suitable mitigation measures to bring those impacts to a level
that would be considered less then significant.
1.2 Project Location
The proposed project is located within the City of Carlsbad, CA. More specifically, the
project is located at 341 Oak Avenue between Lincoln Street and Washington Street,
west of Interstate 5 in the City of Carlsbad CA. Access to the project site would be
taken from Carlsbad Village Drive to the north and Carlsbad Boulevard to the west. A
general project vicinity map is shown in Figure 1-1 on the following page.
1.3 Project Setting
The proposed project consists of eight (8) three-story unit residential townhomes on
approximately 0.4 acres. The existing site conditions are characterized as mostly
disturbed land with existing residential structures onsite that will be removed. The
general topography of the site is characterized as relatively flat. The site is surrounded
by existing multi-family structures. A project site plan is shown in Figure 1-2 on Page 3
of this report.
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Ldn Consulting, Inc. 4/17 /18 1829-02 341 Oak Avenue Noise Report
Figure 1-1: Project Vicinity Map
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1829-02 341 Oak Avenue Noise Report
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Figure 1-2: Project Site Plan
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Ldn Consulting, Inc. 4/17/18 1829·02 341 Oak Avenue Noise Report
2.0 ACOUSTICAL FUNDAMENTALS
Noise is defined as unwanted or annoying sound which interferes with or disrupts
normal activities. Exposure to high noise levels has been demonstrated to cause hearing
loss. The individual human response to environmental noise is based on the sensitivity
of that individual, the type of noise that occurs and when the noise occurs.
Sound is measured on a logarithmic scale consisting of sound pressure levels known as
a decibel (dB). The sounds heard by humans typically do not consist of a single
frequency but of a broadband of frequencies having different sound pressure levels.
The method for evaluating all the frequencies of the sound is to apply an A-weighting to
reflect how the human ear responds to the different sound levels at different
frequencies. The A-weighted sound level adequately describes the instantaneous noise
whereas the equivalent sound level depicted as Leq represents a steady sound level
containing the same total acoustical energy as the actual fluctuating sound level over a
given time interval.
The Community Noise Equivalent Level (CNEL) is the 24 hour A-weighted average for
sound, with corrections for evening and nighttime hours. The corrections require an
addition of 5 decibels to sound levels in the evening hours between 7 p.m. and 10 p.m.
and an addition of 10 decibels to sound levels at nighttime hours between 10 p.m. and
7 a.m. These additions are made to account for the increased sensitivity during the
evening and nighttime hours when sound appears louder.
Another metric that is reported for aircraft and trains is the Single Event Noise
Equivalent Level (SENEL) sometimes referred to as the single event level (SEL). The
SENEL value is the integration of all the acoustic energy contained within the event.
The SENEL metric takes into account the maximum noise level of the event and the
duration of the event. For aircraft and trains, the SENEL value is typically about 10 dBA
higher than the maximum noise level. Single event metrics are a convenient method for
describing noise from individual events. In addition, cumulative noise metrics such as
LEQ and CNEL can be computed from the SENEL data.
A transportation related noise level is from a combination of the noise produced by the
engine, exhaust and tires or wheels. The cumulative traffic noise levels along a roadway
segment are based on three primary factors: the amount of traffic, the travel speed of
the traffic, and the vehicle mix ratio or number of medium and heavy trucks. The
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Ldn Consulting, Inc. 4/17 /18 1829-02 341 Oak Avenue Noise Report
intensity of traffic noise is increased by higher traffic volumes, greater speeds and
increased number of trucks.
Because mobile/traffic noise levels are calculated on a logarithmic scale, a doubling of
the traffic noise or acoustical energy results in a noise level increase of 3 dBA.
Therefore, the doubling of the traffic volume, without changing the vehicle speeds or
mix ratio, results in a noise increase of 3 dBA. Mobile noise levels radiant in an almost
oblique fashion from the source and drop off at a rate of 3 dBA for each doubling of
distance under hard site conditions and at a rate of 4.5 dBA for soft site conditions.
Hard site conditions consist of concrete, asphalt and hard pack dirt while soft site
conditions exist in areas having slight grade changes, landscaped areas and vegetation.
On the other hand, fixed/point sources radiate outward uniformly as it travels away
from the source. Their sound levels attenuate or drop off at a rate of 6 dBA for each
doubling of distance.
The most effective noise reduction methods consist of controlling the noise at the
source, blocking the noise transmission with barriers or relocating the receiver. Any or
all of these methods may be required to reduce noise levels to an acceptable level.
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Ldn Consulting, Inc. 4/17/18 1829-02 341 Oak Avenue Noise Report
3.0 SIGNIFICANCE THRESHOLDS AND STANDARDS
The City of Carlsbad's General Plan Noise Element requires that all exterior sensitive areas
shall limit noise exposure. Table 3-1 below (Table 5-2 of the General Plan) indicates
acceptable limits of noise for various land uses for both exterior and interior environments
from transportation sources. While Table 5-1 of the Noise Element establishes standards
to help the city determine the appropriateness of locating specific uses in noise-prone
environments, Table 5-2 provides standards that development shall attain through noise
attenuation measures.
Table 3-1: Allowable Noise Exposure1
Land Use Outdoor Activit/ 3 Interior Spaces
Areas (dBA CNEL) (dBA CNEL)
Residential 604 45
Motels, Hotels 65 45
Hospitals, Residential care
Facilities, Schools, Libraries, 65 45 Museums, Churches, Day care
Facilities
Playgrounds, Parks, Recreation 65 50 Uses
Commercial and Office Uses 65 50
Industrial Uses 70 65
1 Development proposed within the McClellan-Palomar Airport Area of Influence
shall also be subject to the noise compatibility policies contained in the ALUCP.
2 For non-residential uses, where an outdoor activity area is not proposed, the
standard does not apply. Where the location of outdoor activity areas is
unknown, the exterior noise level standard shall be applied to the property line
of the receiving use.
3 Where it is not possible to reduce noise in outdoor activity areas to the allowable
maximum, levels up to 5 dB higher may be allowed provided that available
exterior noise level reduction measures have been implemented and interior
noise levels are in compliance with this table.
4 An exterior noise exposure level of 65 dBA CNEL is allowable for residential uses
in a mixed-use project and for residential uses within the McClellan-Palomar
Airport Area of Influence, pursuant to the noise compatibility policies contained
in the ALUCP.
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For noise sensitive residential land uses, the City has adopted a policy which has
established a "normally acceptable" exterior noise level goal of 60 dBA CNEL for the
outdoor areas and an interior noise level of less than 45 dBA CNEL. For residential
properties identified as requiring a noise study, the study shall document the projected
maximum exterior noise level and mitigate the projected exterior noise level to a
maximum allowable noise level as identified in the Noise Element. If the acoustical
study shows that exterior noise levels cannot be mitigated to the level allowable as
identified in this policy or less, the development should not be approved without one or
more of the following findings:
(1) Changes or alterations have been required in/ or incorporated into/ the project which avoid
or substantially lessen the significant environmental effect (noise).
(2) Changes or alterations to avoid or substantially lessen the significant environmental effect
(noise) are within the responsibility and jurisdiction of another public agency and not the City of
Carlsbad. Such changes have been adopted by such other agency or can and should be
adopted by such other agency.
(3) Specific economi~ social, or other considerations make infeasible the mitigation measures
or project alternatives to avoid or substantially lessen the significant environmental effect
(noise).
If a project is approved with exterior noise levels exceeding the level allowable pursuant
to this policy, all purchasers of the impacted property shall be notified in writing prior to
purchase, and by deed disclosure in writing, that the property they are purchasing is, or
will be, noise impacted and does not meet Carlsbad noise standards for residential
property.
California Noise Insulation Standards (California Code of Regulations, Title 24) and the
City of Carlsbad Noise Element establish an interior noise standard of 45 dBA for
residential structures. Acoustical studies must be prepared for residential structures that
are proposed to be located within the Community Noise Equivalent Level (CNEL) noise
contours of 60 dBA or greater. In addition, the City requires residential structures
located within the CNEL noise contours of 60 or greater to prepare an acoustical study.
The studies must demonstrate that the building is designed to reduce interior noise to
45 dBA or lower (CNEL).
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Ldn Consulting, Inc. 4/17/18 1829-02 341 Oak Avenue Noise Report
4.0 NOISE ENVIRONMENT
4.1 Existing Noise Environment Onsite
Noise measurements were taken Friday March 27, 2018, using a Larson-Davis Model
LxT Type 1 precision sound level meter, programmed, in "slow" mode, to record noise
levels in "A" weighted form. The sound level meter and microphone were mounted on a
tripod, five feet above the ground and equipped with a windscreen during all
measurements. The sound level meter was calibrated before and after the monitoring
using a Larson-Davis calibrator, Model CAL 200. Monitoring location 1 (Ml) was located
at the northwest end of the project along Oak Avenue. The results of the noise level
measurement are presented in Table 4-1.
The noise measurements were monitored for a time period of 15 minutes during normal
traffic conditions. The existing noise levels in the Project area consisted primarily of
residential activities, a half a dozen vehicles along the adjacent roadway and some
background noise from traffic along Carlsbad Village Drive and Carlsbad Boulevard . The
ambient Leq noise level measured in the area of the Project was found to be 58 dBA.
Table 4-1: Measured Ambient Noise Levels
Measurement
Identification
Ml
Description Time
Oak Avenue 7:15-7:30 a.m. 58.1
Source: Ldn Consulting, Inc. March 27, 2018
76.4
Noise Levels (dBA)
Lmin
48.7 58.9 51.2 49.5
Due to the close proximity of Oak Avenue the overall sound level was found to be 58.1
dBA CNEL. The statistical indicators LlO, L50, and L90, are given for the monitoring
results. As can be seen from the L90 data, 90% of the time the noise level is less than
50 dBA CNEL. This is due to the combination of vehicle and train activities. The noise
monitoring locations can be seen in Figure 4-1 below.
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Figure 4-1: Ambient Monitoring Locations
Ldn Consulting, Inc., 3/18
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Ldn Consulting, Inc. 4/17 /18 1829-02 341 Oak Avenue Noise Report
4.2 Future Noise Prediction Methodology
Roadway Noise Level Assessment
The projected roadway noise levels from vehicular traffic were calculated using the
methods in the Highway Noise Model published by the Federal Highway Administration
(FHWA Highway Traffic Noise Prediction Model, FHWA-RD-77-108, December, 1978). The
FHWA Model uses the traffic volume, vehicle mix, speed, and roadway geometry to
compute the equivalent noise level. A spreadsheet calculation was used which computes
equivalent noise levels for each of the time periods used in the calculation of CNEL.
Weighting these equivalent noise levels and summing them gives the CNEL for the traffic
projections.
Mobile noise levels radiant in an almost oblique fashion from the source and drop off at
a rate of 3 dBA for each doubling of distance under hard site conditions and at a rate of
4.5 dBA for soft site conditions. Hard site conditions consist of concrete, asphalt and
hard pack dirt while soft site conditions exist in areas having slight grade changes,
landscaped areas and vegetation.
According to the City of Carlsbad General Plan Noise Element, the unshielded future year
2035 noise levels along Carlsbad Boulevard and Carlsbad Village Drive are expected to be
64 dBA CNEL at 100-feet from the roadway centerlines. The project is located
approximately 420-feet from the centerline of Carlsbad Boulevard and 520-feet from the
centerline of Carlsbad Village Drive. The noise reduction due to distance would result in
unshielded future noise levels at the site of 55 dBA CNEL from the centerline of Carlsbad
Boulevard and 53 dBA CNEL from the centerline of Carlsbad Village Drive. It should be
noted, the line of sight to the roadways is primarily blocked by numerous residential
structures which would result at least a 10 decibel reduction in noise levels in accordance
with Caltrans Technical Noise Supplement. Due to the distance of the noise sources and
the shielding from the existing structures, the resultant noise levels would not have a
cumulative effect at the project site.
Railroad Noise Level Assessment
The San Diego Northern Railway (SDNR) segment located approximately 260-feet
northeast of the project site is utilized for both commuter trains (Coaster and Surfliner)
and a few freight trains. According to the City of Carlsbad General Plan Noise Element,
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the 60 dBA CNEL noise contour from the rail activity, with no shielding, is located 250
feet from the centerline of the railroad.
Cumulative Noise Levels
Due to the distance of the roadways and the shielding from the existing structures, the
resultant noise levels from the roadways would not have a cumulative effect at the project
site. Therefore, a worst-case cumulative noise level of 60 dBA CNEL, from the rail
activity, is anticipated at the project site. No exterior noise mitigation is required to
meet the City's 60 dBA CNEL threshold.
Additionally, due to the project's relation to the railway, full disclosers must be posted
and given to potential tenants or buyers according to the City of Carlsbad Noise
Guidelines Manual Land Use Section C.5 as stated: Enforce the policy of the City that 60
dBA CNEL is the exterior noise level to which all residential units should be mitigated.
Additional disclosure actions (easements, deed restrictions, recorded notice, etc.) may
be required of developers/sellers of noise impacted residential units.
4.3 Interior Noise Methodology
The methodology used to determine the resultant interior noise levels is based upon the
exterior noise level minus the sound transmission loss as identified in the American
Society of Testing and Materials (ASTM) guidelines: E413 &E90. Standard building
construction will provide a noise reduction of approximately 12-15 dBA with a windows
open condition and a minimum 20 dBA noise reduction with the windows closed. The
exterior noise levels at the proposed structures calculated in terms of dBA are
converted to the six octave band sound pressure levels between: 125 -4000 Hertz.
Acoustical modeling of the proposed project was performed in accordance with the
above guidelines and included combining the transmission loss for each of the building
components that will reduce the interior noise levels. Building components typically
include the windows, exterior doors, and exterior walls. The total noise reduction is
dependent upon the transmission loss of each building component, their subsequent
surface area, quality of the building/construction materials, a building fa~ade and angle
correction. The interior noise level is also dependent on the acoustical energy absorbed
within the room based upon the Noise Reduction Coefficients (NRC). NRC is a scalar
representation of the amount of sound energy absorbed upon striking a particular
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Ldn Consulting, Inc. 4/17/18 1829·02 341 Oak Avenue Noise Report
surface and the arithmetic value average of sound absorption coefficients indicating a
material's ability to absorb sound. The absorption coefficients for individual surface
areas such as carpet, drywall and furnishings are used to calculate the interior room
effects. The calculated building noise reduction includes both the room absorption
characteristics and the transmission loss from the exterior wall assembly.
The interior noise reduction calculations were performed using Ldn's interior noise
model. The model converts the exterior sound level to octave band frequencies and
accounts for the transmission loss, correction factors and room absorption. The floor
plans used for this analysis were provided by D33 Design & Planning, dated February
2018. The following construction details were utilized for each of the building assemblies
to determine the noise reduction characteristics:
Exterior walls must have a Sound Transmission Class (STC) rating of 36 or better. Exterior
walls with this rating consist of 2"x4" studs or larger, spaced 16" o.c. with R-13 insulation
minimum and an exterior surface of 1/4" lap siding or 7/8" cement plaster (stucco).
Interior wall and ceiling surfaces shall be at least 1/2" thick gypsum or plaster. Roof
assemblies should have a minimum of 1/2" sheathing, R-19 insulation and sealed to
prevent noise leaks. Exterior entry doors should be of solid core construction and glass
assemblies should be dual-glazed and acoustical sealant applied around the exterior
edges. The window and door assemblies are generally the weakest noise reducing
component but are the most convenient and cost effective elements to change if
additional attenuation is needed. The STC ratings for the glass assemblies and exterior
entry doors were calculated in the interior noise model and provided in the findings
below.
Bathrooms, kitchens, closets and corridors are not required to meet the 45 dBA CNEL
standard and therefore were not modeled. All living areas, this includes bedrooms, living
rooms and dining rooms were modeled to determine the interior noise reductions. If the
modeled interior noise levels were found to be higher than 45 dBA CNEL in the living areas
with the minimum assembly requirements described above additional modeling was
performed to determine the minimum STC rating for the glass assemblies to further
reduce interior noise levels below the acceptable interior threshold of 45 dBA CNEL.
12
Ldn Consulting, Inc. 4/17 /18 1829-02 341 Oak Avenue Noise Report
The exterior noise levels were determined to be as high as 60 dBA CNEL from railroad and
traffic sources. To meet the 45 dBA CNEL interior noise standard, an overall minimum
interior noise level reduction of 15 dBA CNEL is needed for the proposed project. The
necessary Sound Transmission Class and transmission losses for all glass assemblies
and entry doors of the residential units located nearest the SDNR railroad are provided
in Table 4-2. The modeled results with an anticipated interior noise level of 45 dBA
CNEL or less are provided as an Attachmentto this report.
Thus, it is recommend that interior noise reduction methods (i.e., dual-paned glass
treatments) having a sound transmission classification (STC) rating of 26 or higher be
installed to reduce the noise levels.
Table 4-2: Sound Transmission Class Ratings
STC Octave Band Transmission Loss (Hz)
Assembly Rating1
125 250 500 1000 2000 4000
Windows 26 21 20 23 25 29 32
Fixed Windows 26 17 16 22 31 35 27
Glass Doors 26 21 24 27 27 24 28
1 STC Ratings used in Model
13
Ldn Consulting, Inc. 4/17/18 1829-02 341 Oak Avenue Noise Report
Appendix A
INTERIOR NOISE MODEL CALCULATION
INTERIOR NOISE CALCULATIONS
Project Name: 341 Oak Ave
Building (s) All
Floor Level 1
Arch Plan: 1
Room Type: Den
Exterior Noise Levels
Exterior
Assembly Source Area
Stucco NBS W-50-71 180
Windows Milgard 30
Fixed Window Milgard 0
Glass Doors Milgard 0
Exterior Door NBS Monograph 77 0
Room Absorption (RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fa<;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-19.2 -19.2
15.7 15.7
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project# 18-29
Transmission Loss { dB J
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-19.2 -19.2 -19.2 -19.2
15.7 15.7 15.7 15.7
25.6
60.0
Resultant Interior Noise Level (dBA CNEL) 34
* Corrections for Fa,ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name: 341 Oak Ave
Building (s) All
Floor Level 1
Arch Plan: 1
Room Type: Living/Dining
Exterior Noise Levels
Exterior
Assembly Source Area
Stucco NBS W-50-71 306
Windows Milgard 90
Fixed Window Milgard 0
Glass Doors Milgard 0
Exterior Door NBS Monograph 77 0
Room Absorption (RA)
Interior
Characteristics Source
carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC 125
46 27
26 21
26 17
26 21
28 16
NRC 125
0.28 0.15
0.45 0.32
0.07 0.09
0.8 0.56
125
-22.6
16.5
ce Exposure Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fa~ade Noise Level (dBA CNEL)
250
42
20
16
24
14
250
0.17
0.29
0.08
0.54
250
-22.6
16.5
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-22.6 -22.6 -22.6 -22.6
16.5 16.5 16.5 16.5
21.5
60.0
Resultant Interior Noise Level (dBA CNEL) 38
* Corrections for Fa~ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
2
1
Master Bedroom
Exterior Noise Levels
Exterior
Assembly Source
Stucco NBS W-50-71
Windows Milgard
Fixed Window Milgard
Glass Doors Milgard
Exterior Door NBS Monograph 77
Room Absorption (RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Fu rnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
252
35
0
0
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fa<;ade Noise Level (dBA CNEL)
* Corrections for fa~ade Level was accounted for in the modeling.
250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-21.0 -21.0
16.0 16.0
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-21.0 -21.0 -21.0 -21.0
16.0 16.0 16.0 16.0
26.6
60.0
INTERIOR NOISE CALCULATIONS
Project Name: 341 Oak Ave
Building (s) All
Floor Level 2
Arch Plan: 1
Room Type: Bedroom 2
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption (RA}
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
162
30
0
0
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fai;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-19.2 -19.2
15.7 15.7
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project# 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-19.2 -19.2 -19.2 -19.2
15.7 15.7 15.7 15.7
25.7
60.0
Resultant Interior Noise Level (dBA CNEL) 34
* Corrections for Fa~ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
2
2
Great Room
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption {RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
423
45
0
48
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fai:,;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-26.8 -26.8
17.8 17.8
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-26.8 -26.8 -26.8 -26.8
17.8 17.8 17.8 17.8
25.2
60.0
Resultant Interior Noise Level (dBA CNEL) 35
* Corrections for Fa~ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
2
2
Bedroom 4
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption (RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
225
35
0
0
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fa<;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-21.3 -21.3
15.9 15.9
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-21.3 -21.3 -21.3 -21.3
15.9 15.9 15.9 15.9
27.0
60.0
Resultant Interior Noise Level (dBA CNEL) 33
* Corrections for Fac;ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
3
2
Master Bedroom
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption (RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
261
20
0
64
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fac_;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-22.2 -22.2
17.4 17.4
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-22.2 -22.2 -22.2 -22.2
17.4 17.4 17.4 17.4
24.3
60.0
Resultant Interior Noise Level (dBA CNEL) 36
* Corrections for Fa~ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
3
2
Bedroom 3
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption {RA)
Interior
Characteristics Source
Carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
216
30
0
0
0
Noise Reduction from Absorption based upon Floor Area
Noise Level I ncrease for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fa<;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-20.3 -20.3
15.8 15.8
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-20.3 -20.3 -20.3 -20.3
15.8 15.8 15.8 15.8
26.6
60.0
Resultant Interior Noise Level (dBA CNEL) 33
* Corrections for Fa~ade Level was accounted for in the modeling.
INTERIOR NOISE CALCULATIONS
Project Name:
Building (s)
Floor Level
Arch Plan:
Room Type:
341 Oak Ave
All
3
2
Den
Exterior Noise Levels
Exterior
Assembly
Stucco
Windows
Fixed Window
Glass Doors
Exterior Door
Source
NBS W-50-71
Milgard
Milgard
Milgard
NBS Monograph 77
Room Absorption (RA)
Interior
Characteristics Source
carpet Army TM 5-805-4
Furnishings Army TM 5-805-4
Drywall Netwell
Overall Absorption Factor (Furnished Room)
Noise Reduction
Area
90
20
0
0
0
Noise Reduction from Absorption based upon Floor Area
Noise Level Increase for Defects and Exposed Surface Area
STC
46
26
26
26
28
NRC
0.28
0.45
0.07
0.8
Overall Reduction from Tranmission Loss + Room Absorption -Surfa
Building Fac;ade Noise Level (dBA CNEL)
125 250
27 42
21 20
17 16
21 24
16 14
125 250
0.15 0.17
0.32 0.29
0.09 0.08
0.56 0.54
125 250
-20.4 -20.4
15.1 15.1
ce Exposure
Ldn Consulting, Inc.
Date: 4/16/18
Project # 18-29
Transmission Loss {dB}
Frequency {Hz.}
500 1000 2000 4000
44 46 49 54
23 25 29 32
22 31 35 27
27 27 24 28
23 30 36 26
Absorption Coefficients
Frequency {Hz.}
500 1000 2000 4000
0.12 0.32 0.52 0.30
0.42 0.58 0.60 0.48
0.05 0.03 0.06 0.09
0.59 0.93 1.18 0.87
500 1000 2000 4000
-20.4 -20.4 -20.4 -20.4
15.1 15.1 15.1 15.1
28.8
60.0
Resultant Interior Noise Level (dBA CNEL) 31
* Corrections for Fa<;ade Level was accounted for in the modeling.