P2542 Kevin Manley - Summary Report for Home Exterior Noise Reduction Review, Sep 16, 2020 ver 1) esi engineering
September 16, 2020
Mr. Kevin Manley
6238318 th Street
Canon Falls, MN 55009
Subject: Summary Report for
Home Exterior Noise Reduction Review
Eagan, Minnesota
Dear Mr. Manley:
We understand that you are planning to develop a residential neighborhood of 10 homes near
the West End Trap Club in Eagan, Minnesota. Stone Cottage Construction is the general
contractor. Because the new homes will be close to the West End Gun Club, we understand the
City of Eagan is requiring you to show that the exterior fagade of the houses provide at least
13 dBA of noise reduction so that gun club noise inside the homes is below 45 dBA. As shown
in the aerial photo below, the new development is south of the gun club property. The City has
asked you to provide a letter confirming that the noise requirements will be met prior to issuing
building permits. ESI has reviewed the construction documents to evaluate the noise reduction
of the exterior walls and windows. This letter is a summary of our findings.
Figure 1 - Aerial view of the West End Trap Club and the Manley residential development.
Structures I Vibration I Noise I Monitoring
ESI Engineering Inc. 7831 Glenroy Road Suite 218, Minneapolis, MN 55439
952.831.4646 1 esi-engineering.com
Mr. Kevin Manley September 16, 2020
Home Exterior Noise Reduction Review Page 2
Basis of Analysis
In April 2019, ESI performed a noise study at the site while the gun range was in use to
determine the club noise levels (see Figure 1 for measurement location). ESI made
recommendations for mitigation of the gun club noise to meet the State of Minnesota Shooting
Range Protection Act requirements for outdoor noise at the development.
To evaluate noise inside the new homes, the gun range measurement data for the loudest hour
(1OAM-11AM) with the proposed mitigation (barrier wall on berm) were used to determine if
the 13 dBA reduction and 45 dBA level will be achieved by the window and wall assemblies that
are in the design. The loudest hourly equivalent continuous noise level (Leq) measured outside
while the gun club was in use was 67 dBA, and the level with the barrier wall and berm in place
was 58 dBA. We evaluated noise inside houses 3 and 4 shown in Figure 1, which are nearest
the four shooting areas.
Based on the drawings provided for the homes, we understand that the exterior wall assembly
will consist of the following elements, listed from the house exterior to the interior:
• Vinyl siding and house wrap
• 7/16" oriented strand board (OSB) wall sheathing
• 2 x 6 wood studs spaced 16" o.c. and filled with R-21 batt insulation
• 1/2" -thick gypsum board
This wall assembly is estimated to have a sound transmission class (STC1) rating of STC 37Z.
We also understand that the windows and patio doors will be rated at STC 273. These
assemblies, their respective STC ratings, and the area of each were used to calculate composite
STC ratings (STCc4) for rooms in the house for which we evaluated the expected noise level
inside.
As defined in ASTM standard C634-13, Sound Transmission Class, or STC, is "a single -number rating calculated
in accordance with Classification E413 using values of sound transmission loss. It provides an estimate of the
performance of a partition in certain common sound insulation problems." It is based on laboratory tests of wall
and floor/ceiling assemblies that serve as acoustical barriers, with higher values representing better insulation.
Z Test number TLA -99-029a NRC-CNRC, IRC -IR -181, Laboratory Measurements of the Sound Insulation of Building Fagade
Elements.
3 From the window manufacturer.
4 Composite STC rating, or STCc, is the overall STC rating of an entire partition, including the wall, doors, windows
or other penetrations or openings. Fenestration or penetrations usually reduce the composite STC rating of a
partition since they are weaker points for noise transmission in the assembly.
Mr. Kevin Manley
Home Exterior Noise Reduction Review
Outdoor to Indoor Noise Calculations
September 16, 2020
Page 3
Calculations were prepared to determine outdoor noise transmission into two different spaces
in the houses closest to and facing the gun club (houses 3 and 4, similar distance to all four
shooting areas). We evaluated the noise level in the open space on the main level made up of
the dining area, kitchen, and great room. We also evaluated the noise level inside the master
bedroom on the second level.
The dimensions and current architectural finishes for these spaces were used in the calculations
to determine the room effect on the transmitted noise. The dimensions and areas of the exterior
fagade shared with these rooms was also used to determine the STCc of the exterior fagade.
Detailed calculations are provided in Attachment A.
The calculated noise reduction from the exterior fagade and the interior noise levels are shown
in Tablel below. In both spaces evaluated, the City of Eagan requirements are met. No
modifications to the exterior fagade are needed.
Table 1 — Outdoor to Indoor Noise Calculation Results
Calculated Noise
City of Eagan
Calculated Interior Noise Level
City of Eagan
Reduction from
Required
from Loudest Gun Club Hour
Required Interior
Room Evaluated
Exterior Fagade
Reduction
(10-11 AM)
Noise Level
Dining / Kitchen /
25 dBA
33 dBA
Great Room
13 dBA
45 dBA
Master Bedroom
26 dBA
32 dBA
Mr. Kevin Manley
Home Exterior Noise Reduction Review
Conclusions
September 16, 2020
Page 4
ESI was asked to evaluate the exterior noise reduction for the proposed residential development
site south of the West End Trap Club in Eagan, Minnesota. The City of Eagan has requested that
the fagade provide at least 13 dBA of noise reduction, so that the noise level from the gun range
is below 45 dBA inside the homes.
Our calculations evaluated the noise reduction provided by the fagade at two different locations
inside a worst-case (closest to the gun club) house. We found that the fagade provides
25 to 26 dBA of noise reduction, meaning the expected noise levels inside the house from the
loudest hour of gun club noise to be 32 to 33 dBA. This meets the City of Eagan requirements
and no modifications are needed to the exterior fagade design.
We appreciate the opportunity to work with you on this project and remain available to assist
in the resolution of these and any other matters. Please let us know if you have any questions
or need more information.
Sincerely,
A01 Ze.
Andrew A.J. Schmitt
Consulting Engineer
ESI Engineering, Inc.
Attachments
Anthony J. Baxter, P.E.
Principal
ESI Engineering, Inc.
File: P2542 Kevin Manley - Summary Report for Home Exterior Noise Reduction Review, Sep 16, 2020 ver 1
Attachment A
Outdoor -Indoor Noise Transmission Calculations
Home Exterior Noise Reduction Review - September 16, 2020
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
Home Exterior Noise Reduction Review
September 16, 2020
Calculations by: AAJS
Checked by: AJB
We understand that Mr. Kevin Manley is developing a residential neighborhood of 10 homes near the West End
Trap Club in Eagan, Minnesota. Because the new homes will be close to the West End Gun Club, we understand
the City of Eagan is requiring Mr. Manley to show that the exterior facade of the houses provide at least 13 dBA of
noise reduction so that gun club noise inside the homes is below 45 dBA.
ESI Engineering Client: Kevin Manley September 16, 2020
7831 Glenroy Road, Suite 218 Project: P2541 Calculations by: AAJS
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review Checked by: AJB
Noise Control Constants
1/3 Octave dBA Scale Air Attenuation: Octave Band Noise Criterion (NC)
Bands Used: Corrections: (Hansen, pg 157) Curve Sound Pressure Levels:
P= I
50
-30.2
0.0
63
-26.2
0.1
80
-22.5
0.1
100
-19.1
0.2
125
-16.1
0.3
160
-13.4
0.5
200
-10.9
0.8
250
-8.6
1.1
315
-6.6
1.9
400
dBA:=
-4.8
m:-
2.6
500
-3.2
3.4
630
-1.9
4.7
800
-0.8
6.1
1000
0.0
7.4
1250
0.6
9.2
1600
1.0
11.0
2000
1.2
12.8
2500
1.3
17.0
3150
1.2
21.2
4000
1.0
25.4
References:
NC := I
47 51 54 57 60 64 67 71 74 77 80
36 40 44 48 52 56 60 64 67 71 75
29 33 37 41 45 50 54 58 62 67 71
22 26 31 35 40 45 49 54 58 63 68
17 22 27 31 36 41 46 51 56 61 66
14 19 24 29 34 39 44 49 54 59 64
12 17 22 28 33 38 43 48 53 58 63
11 16 21 27 32 37 42 47 52 57 62
dB Specific NC -Levels
1000-M
NC15 := NC NC20 := NC NC25 := NC
L L ,� L L, Z L i, 3
NC30 := NC NC35 := NC NC40 := NC
L L� 4 L L A S L !, 6
NC := NC NC50.:= NC NC55.:= NC
i e,7 L C,8 L e,9
NC60 := NC i o NC65 := NC , 11
1. Architectural Acoustics: Principles and Design,
Madan Mehta, James Johnson and Jorge Rocafort, Prentice Hall, 1998
2. Acoustics
Leo L. Beranek, McGraw-Hill Book Company, 1954
3. Sound and Vibration Design and Analysis,
National Environmental Balancing Bureau (NEBB), 1994
4. Noise Control: From Concept to Application,
Colin Hansen, Taylor & Francis, 2005
5. Handbook of HVAC Applications,
American Society of Heating, Regfrigeration and Air -Conditioning Engineers, 2011
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
1. Gun Range Sound Data (Measured on April 28, 2019):
Sound Pressure Level Spectrum (in dB) from Gun Club during loudest hour (10AM - 11AM):
Gun Club Noise Leq:
Leq. LOAM: -
52.2
53.1
55.1
58.0
57.2
57.5
60.9
60.0
59.0
58.0
57.2
56.5
56.3
58.2
59.9
61.4
60.9
60.6
61.1
57.3
Check dBA Level :
dB f=
Leq. dBA.lOAM '— Leq.lOAM + dBA
50
63
80
100
125
160
200
250
315
400
500
630
800
1000
1250
1600
2000
2500
3150
4000
L, dRA_ IOAM.
20
Leq.IOAMJBA'=10 • log E 10
i=1
Leq.IOAM.dBA=70.3 dB(A)
September 16, 2020
Calculations by: AAJS
Checked by: AJB
Gun Club Noise Leq with Barrier Attenuation:
Check dBA Level :
Leq.dBA.gunbarr'— Leq.gunbarr + dBA
L, dRA.,,0alr_
20
10
Leq.gunbarr.dBA := 10 • log E 10
i=1
Leq.gunbarr.dBA=58.2 dB(A)
Since the City of Eagan has requested that a
level of 45 dBA be met inside the house, the
exterior facade needs to provide at least 13 dBA
of reduction.
Hz
6
50
6
63
6
80
6
100
6
125
6
160
7
200
7
250
7
315
Hz Leq.gunbarr'— Leq. lOAM—
9
_
dB f
400
9
500
9
630
11
800
11
1000
11
1250
13
1600
13
2000
13
2500
16
3150
16
4000
Check dBA Level :
Leq.dBA.gunbarr'— Leq.gunbarr + dBA
L, dRA.,,0alr_
20
10
Leq.gunbarr.dBA := 10 • log E 10
i=1
Leq.gunbarr.dBA=58.2 dB(A)
Since the City of Eagan has requested that a
level of 45 dBA be met inside the house, the
exterior facade needs to provide at least 13 dBA
of reduction.
Hz
ESI Engineering Client: Kevin Manley September 16, 2020
7831 Glenroy Road, Suite 218 Project: P2541 Calculations by: AAJS
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review Checked by: AJB
2. Dining / Kitchen / Great Room Sound Absorption Data:
Room Dimensions:
L:=19.4 -ft W:=33.2
-ft H:=
9.1
Surface Absorption
Coefficients:
Gypsum Ceiling:
Carpet Floor:
Wood Floor:
Exterior Glazing:
Gyp on Studs:
(Egan)
(Hann Tucker)
(C.M. Harris)
(Mehta, pg. 408)
(Mehta, pg. 407)
S :=L•W=644 ft2
S :=222.8 ft2
S :=(W•L)-S =421 ft2
S :=130 ft2 S :=((2•L+W)•H)-S
=525 ft2
1
2
3 2
4 5
4
0.37
0.03
0.19
0.27
0.18
0.35
0.05
0.18
0.24
0.15
0.33
0.08
0.17
0.21
0.13
0.31
0.12
0.16
0.18
0.11
0.29
0.15
0.15
0.15
0.10
0.23
0.18
0.14
0.12
0.09
0.16
0.22
0.12
0.08
0.08
0.10
0.25
0.11
0.05
0.07
0.08
0.33
0.11
0.05
0.06
0.07
0.42
0.10
0.04
0.05
a :=
1 0.05
a :=
2 0.50
a :=
3 0.10
a :=
4 0.04
5 0.05
0.05
0.53
0.09
0.04
0.05
0.04
0.57
0.08
0.03
0.05
0.04
0.60
0.07
0.03
0.05
0.05
0.63
0.07
0.03
0.05
0.06
0.67
0.06
0.02
0.04
0.07
0.70
0.06
0.02
0.04
0.08
0.70
0.06
0.02
0.04
0.08
0.70
0.07
0.02
0.04
0.09
0.70
0.07
0.02
0.04
Total Surface Area and Volume:
k:= 1.. 5
Total Surface Area, square feet: Room Volume, cubic feet:
Siora[:= ES Sora[=1943 ft2 V:=L•W•H=5861 ft'
k
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
Total Room Absorption:
Average Absorption in Room
(Ref. Beranek, eq. 10.17):
Z(a •S)
k \ k k
aavg:=
`Moral
aavg =
0.234
0.217
0.205
0.193
0.183
0.16
0.131
0.108
0.108
0.109
0.112
0.113
0.111
0.113
0.119
0.122
0.129
0.132
0.134
0.137
3. Master Bedroom Sound Absorption Data:
Room Dimensions:
Room Constant
(Ref. Beranek, eq. 10.46):
`�roral' aavg
Rmain/loor'=
(1 - aavg)
Rmainfloor =
September 16, 2020
Calculations by: AAJS
Checked by: AJB
594
540
500
465
435
369
294
235
235
238
245
248
244
247
264
270
287
295
301
310
sabins
L:=16.7 -ft W:=14•ft
H:=8.1•ft
Surface Absorption
Coefficients:
Gypsum Ceiling:
Carpet Floor:
Exterior Glazing:
Gyp on Studs:
(Egan)
(Hann Tucker)
(Mehta, pg. 408)
(Mehta, pg. 407)
S :=L- W=234 ft2
S :=L- W=234 ft2
S :=45 ft2
S :=((2•L+W)•H)-S =339 ft2
I
2
3
4 3
0.37
0.03
0.27
0.18
0.35
0.05
0.24
0.15
0.33
0.08
0.21
0.13
0.31
0.12
0.18
0.11
0.29
0.15
0.15
0.10
0.23
0.18
0.12
0.09
0.16
0.22
0.08
0.08
0.10
0.25
0.05
0.07
0.08
0.33
0.05
0.06
0.07
0.42
0.04
0.05
a :=
1 0.05
a :=
2 0.50
a :=
3 0.04
4 0.05
0.05
0.53
0.04
0.05
0.04
0.57
0.03
0.05
0.04
0.60
0.03
0.05
0.05
0.63
0.03
0.05
0.06
0.67
0.02
0.04
0.07
0.70
0.02
0.04
0.08
0.70
0.02
0.04
0.08
0.70
0.02
0.04
0.09
0.70
0.02
0.04
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
Total Surface Area and Volume:
Xotell .Sdrface Area, square feet:
S,,,,/ := E S Stotal = 852 ft
z
k
Total Room Absorption:
Average Absorption in Room
(Ref. Beranek, eq. 10.17):
Era •Sl
k \ k k
aavg:_
Stotal
aavg —
0.196
0.182
0.175
0.171
0.169
0.155
0.14
0.127
0.139
0.157
0.173
0.181
0.189
0.197
0.208
0.217
0.228
0.231
0.231
0.234
Room Volume, cubic feet:
V:= L • W • H= 1894 ft'
Room Constant
(Ref. Beranek, eq. 10.46):
S""',- a,119Rmbed '—
(1 — aavg)
Rmbed =
207
190
181
176
173
156
139
123
138
158
178
189
198
209
224
237
252
256
256
260
September 16, 2020
Calculations by: AAJS
Checked by: AJB
sabins
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
4. Exterior Facade Data:
Surface Areas (sqft):
Dining/Kitchen/Great Room:
Smainfl, = 33.2 • ft • 9.1 • ft = 302 ft2
Transmission Loss (dB):
Exterior Wall, STC 37
(Test Number TLA -99-029a
from NRC-CNRC)
TLWall :=
18
16
17
14
13
19
32
33
32
37
37
35
42
44
51
52
51
49
48
53
(-rLW,11 1
zWall'= 10
l 10 J
(Ref. Hansen, Eq.6.27)
Master Bedroom:
Smbed'=14 • ft • 8.1 -ft = 113 ft2
Exterior Window / Patio Door, STC 27
(Test Number TLA -99-197a from
NRC-CNRC)
TLWin
14
16
19
20
22
19
17
13
19
19
22
26
28
33
36
38
38
40
36
33
H-To J
Lw1
O TW.. := 10
September 16, 2020
Calculations by: AAJS
Checked by: AJB
ESI Engineering Client: Kevin Manley
�IIII�� 7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
5. Dining / Kitchen / Great Room Wall Composite Transmission Loss:
Surface Areas of Exterior Facade Components:
Window Surface Area:
Swin :=107 ft2
Wall Surface Area:
SWall:= SmainJloor - SWin = 195 ft2
Composite Transmission Loss of Wall With Windows and Patio Door:
j:= 1 • • 2 S,total
Swall
:-
SWin
TLmainfloor:= -10 • lob (romp)
Ref. Hansen, Eq.6.9
Ztotal :-
�ZWallzWin I
TLmain. loor -
16.1
16.0
17.6
15.3
14.6
19.0
21.3
17.4
23.1
23.4
26.3
29.6
32.2
36.9
40.3
42.2
42.1
43.6
40.0
37.4
2
E (S.I. " rtotal.)
zcomp:= 2
Y] Stotal.
j=i J
TLwall=
September 16, 2020
Calculations by: AAJS
Checked by: AJB
Ref. Hansen, Eq.6.26
18.0
16.0
17.0
14.0
13.0
19.0
32.0
33.0
32.0
37.0
37.0
35.0
42.0
44.0
51.0
52.0
51.0
49.0
48.0
53.0
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
6. Master Bedroom Wall Composite Transmission Loss:
Surface Areas of Exterior Facade Components:
Window Surface Area: Wall Surface Area:
SWin '- 45 ft' `Wall '- Smbed - SM, - 68 f.t2
Composite Transmission Loss of Wall With Window:
j:= 1 • • 2 SWall
'Stotal '-
`SWin
TLmbed •= -10 • log (Zcomp)
Ref. Hansen, Eq.6.9
ztotal '- �ZWall
ZWin I
TLmbed -
16.0
16.0
17.7
15.5
14.8
19.0
20.8
16.9
22.7
22.9
25.8
29.3
31.8
36.5
39.8
41.8
41.7
43.3
39.6
36.9
2
E (S.I. " rtotal.)
zcomp'- 2
Y1 S.I.
J=1 J
TLwall=
September 16, 2020
Calculations by: AAJS
Checked by: AJB
Ref. Hansen, Eq.6.26
18.0
16.0
17.0
14.0
13.0
19.0
32.0
33.0
32.0
37.0
37.0
35.0
42.0
44.0
51.0
52.0
51.0
49.0
48.0
53.0
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
7. Determine Noise Reduction Provided by the Exterior Facades:
Noise Reduction Calculation (Ref. Beranek, eq. 10.83):
Dining/Kitchen/Great Room Wall Noise Reduction
1
NRmainJloor'- TLmainfloor-10 - log 1 -+ Smainjloor/II
4 Rmainfloor
Noise Reduction Results (dB):
NRmainJloor =
17.3
16.9
18.3
15.8
14.9
18.7
20.2
15.6
21.3
21.6
24.5
27.9
30.5
35.2
38.8
40.8
41.0
42.6
39.1
36.5
Master Bedroom Wall Noise Reduction:
NRmbed'- TLmbed -10 • log 1 -+ 'Smbed
4 imbed
NRmbed =
16.9
16.7
18.3
16.0
15.3
19.1
20.5
16.3
22.4
23.1
26.3
30.0
32.6
37.5
41.0
43.1
43.2
44.8
41.2
38.6
September 16, 2020
Calculations by: AAJS
Checked by: AJB
ESI Engineering Client: Kevin Manley
7831 Glenroy Road, Suite 218 Project: P2541
Minneapolis MN 55439 Calculation: Home Exterior Noise Reduction Review
8. Determine Noise Levels from Gun Club's Loudest Hour in the House Due to the
Exterior Wall Partitions:
Gun Club Loudest Hour Leq in the
Dining/Kitchen/Great Room with
Exterior Facade Noise Reduction (dB):
Leq.mainfloor := Leq.gunbarr — NRmainfloor
Leq.mainfloor =
29
30
31
36
36
33
34
37
31
27
24
20
15
12
10
8
7
5
6
5
Leq.dBA.mainfloor := Leq.mainJloor + dBA
20
Leq.mainfloor.dBA'= 10 • log 10
r=1
Leq.mainfloordBA-33 dB(A)
September 16, 2020
Calculations by: AAJS
Checked by: AJB
Gun Club Loudest Hour Leq in the
Master Bedroom with Exterior Facade
Noise Reduction (dB):
Leg. tubed '= Leq.gunbarr — NRmbed
Leq. tubed =
29
30
31
36
36
32
33
37
30
26
22
18
13
10
8
5
5
3
4
3
Leq.dBA.mbed '= Leq. tubed + dBA
L,Q-dRAfloor. L'eq.dRA.mbed,
20
10 Leq.mbed.dBA 10 • log E10 10
i=1
Leq.mbed.dBA=32 dB(A)
Both of the calculated noise levels meet the 45
dBA requirement of the city. The exterior facade
provides approximately 25 dBA of reduction.