REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 1 of 14

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1 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 1 of Robert Matthews, B.ARCH., O.A.A., A.A.N.B., R.A.I.C. N45 ARCHITECTURE INC. 2nd floor, 43 Eccles Street Ottawa, Ontario Canada K1R 6S3 TEL x 234 FAX robertm@n45.ca Dear Robert, N45 Architecture Inc. 852 Bank Street Project HVAC Mechanical Environmental Noise Study We have completed an environmental noise study of the HVAC mechanical equipment on the rooftop of the proposed commercial building at 852 Bank. St. in Ottawa. The purpose of our study is to assess the potential noise impact from rooftop mechanical equipment (4 identical Rooftop Units) to the nearest residential buildings. The following drawings and data were used for this report: Architectural drawings for Bank & Fifth Ave, Ottawa, ON Site Study, dated October 15, 2013, October 17, 2013 and March 31, Preliminary Service Summation Sheet and Manufacturer s Sound Power Level data for 4 identical Roof Top Units (RTUs) based on York Predator RTU ZH120N15P2AAA5 Based on this information, we have created a 3D model of the proposed commercial building at 852 Bank St. and have calculated the worst-case predicted noise levels at the 4 nearest residential buildings: Apartment buildings at 147 & th Ave, the Church at 2 Monk St. and the house at 5 Monk St. The calculated Sound Pressure Levels (SPL) at the two nearest Points of Reception (POR) at 147 & th Ave are 58 dba and 61 dba, which are above the City of Ottawa By-Law limit of 50 dba. In order to keep the sound pressure levels at these residential buildings below the noise by-law limits, our recommendation is to do both of the following: 1. Select quieter RTUs (maximum outdoor casing radiated sound power levels of 81 dba) 2. Place the RTUs in the middle of the roof, as far away as possible from the neighbouring residential buildings. Should you have any questions regarding this report, please do not hesitate to contact us. Sincerely, Peter Wright, M.Sc. Acoustic Consultant

2 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 2 of 14 Environmental Noise Study for 852 Bank St., Ottawa, Ontario Prepared for: N45 Architecture Inc. Prepared by: Peter Wright, M.Sc. June 2, 2014

3 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 3 of 14 Contents 1. Introduction Site Description and By-Law Requirements Operation hours for the Facility Site Plan and Scaled Area Location Plan Noise By-Law Noise Sources Significant Noise Sources Noise Source Summary Table Points of Reception Methodology Used in Noise Impact Calculation Procedure Used to Assess Noise Impact at Each Point of Reception Other Parameters/Assumptions Used in Calculations Acoustic Assessment Summary Acoustic Assessment Summary for All Equipment with no Noise Mitigation Noise Control Measures and Recommendations Conclusion Appendix A Manufacturer Sound Power Level Data for RTUs... 14

4 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 4 of Introduction State of the Art Acoustik Inc. has been commissioned by N45 Architecture Inc. to complete an environmental noise study for a 2 story commercial building to be located at 852 Bank St. in Ottawa, Ontario. This building will be constructed in an area that has a mix of commercial and residential buildings. Due to the building s proximity to local residences, this report s environmental noise assessment and design recommendations will ensure adherence to the City of Ottawa s noise by-law. This by-law states that the total sound pressure level from all mechanical equipment must be below 50 dba SPL, or the existing background noise level (whichever is higher), at any sensitive points of reception (By-law no ). This assessment assumes the mechanical equipment operates at all times. There are four identical 10 ton Rooftop Units that are being considered for this assessment. A description of the facility is provided below. 2. Site Description and By-Law Requirements The proposed commercial building at 852 Bank St. is divided into two sections with differing elevations: one 4m tall section with a proposed roof top patio (evaluated in a separate report) and one 9m tall section, with two stories of commercial space and the HVAC mechanical equipment on the roof. The building will be located in a neighbourhood that contains a mix of commercial and residential buildings. Mechanical plans have not yet been finalized and the location of the 4 RTUs has not yet been decided, so we have considered the worst-case scenario where all mechanical equipment is located at the edge of the roof closest to the PORs. 2.1 Operation hours for the Facility The Rooftop Units are assumed to run 24 hours a day 7 days a week. 2.2 Site Plan and Scaled Area Location Plan Figure 2.1 on the following page shows a site map of the proposed commercial building at 852 Bank St. and the closest points of reception taken from the City of Ottawa GeoOttawa map service.

REP N45 852 BANK ST. ENVIRONMENTAL NOISE STUDY Page 5 of 14 POR 1: 147 5 th Ave POR 2: 149 5 th Ave POR 3: 2 Monk St. 852 Bank St. Proposed Commercial Building Property Line.

5 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 5 of 14 POR 1: th Ave POR 2: th Ave POR 3: 2 Monk St. 852 Bank St. Proposed Commercial Building Property Line. Blue dashed line designates edge of 2 nd level rooftop (patio located on first level rooftop, closest to 5 th Ave.). Figure 2.1 Site map of 852 Bank St. and closest residential Points of Reception. Map taken from Noise By-Law POR 3: 5 Monk St. The City of Ottawa noise by-law no states: No person shall use or operate or cause to be used or operated any exhaust fan, exhaust system, intake fan, generators, dryer in a commercial car wash or similar device which includes combustion exhaust of a high efficiency furnace, the noise from which has a level greater than 50 dba when measured at the point of reception. Where the "point of reception" means any point on the premises of a person where sound or vibration originating from other than those premises is received; For our analysis, the points of reception are chosen based on the principle of "predictable worst case scenario" for noise impact. This will allow us to calculate the largest noise impact and mitigate it accordingly.

6 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 6 of Noise Sources The following section describes the characteristics of the significant noise sources. 3.1 Significant Noise Sources This report evaluates four significant noise sources: 4 identical RTUs. Tables and summarize the sound power levels for the Rooftop Units (RTUs). Significant Sources RTU Manufacturer Model/Series Quantity Manuf. Sound Levels (dba) Calc. Sound Power Level (dba) Predator York 4 91 SWL 91 SWL ZH120N15P2AAA5 Table Summary of Noise Sources used in this Analysis. Noise Source 63 Hz. 125 Hz. 250 Hz. 500 Hz. 1 KHz. 2 KHz. 4 KHz. 8 KHz. RTU Table Octave Band Sound Power Levels of Noise Sources in dba. The Preliminary Service Summation Sheet provided by the mechanical contractor listed two Makeup Air Units (MAU) in addition to the RTUs, however it was confirmed by the contractor that the MAUs will no longer be used. If they are added at a later date, we will need to bill for re-analysis and re-issuing of the report. The manufacturer s data sheets for the RTUs are included in the Appendix. Total dba

7 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 7 of Noise Source Summary Table Source Description Source Location 1 Sound Characteristics 2 Noise Control Measures 3 Sound Power Level (dba) Rooftop Unit O S U 91 Table 3.2 Acoustical Information for each significant source included in this study. 1. Source Location: O - located/installed outside the building, including on the roof I - located/installed inside the building 2. Sound Characteristics: S: Steady Q: Quasi Steady Impulsive I: Impulsive B: Buzzing T: Tonal C: Cyclic 3. Noise Control Measures S: silencer, acoustic louver, muffler A: acoustic lining, plenum B: barrier, berm, screening L: lagging E: acoustic enclosure O: other U: uncontrolled

8 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 8 of Points of Reception Points of reception have been selected by using worst case situations for the following types of development: permanent or seasonal residences, hotels/motels, nursing/retirement homes, rental residences, hospitals, camp grounds, and noise sensitive buildings such as schools and places of worship. We have chosen the four most sensitive Points of Reception (POR) for the noise level analysis, which are illustrated in figure 2.1 on page 5. The minimum distances from the source building to the points of reception are stated below: POR th Ave. apartment building, 20m to the North (3 rd level, 11m above ground) POR th Ave. apartment building, 20m to the North (3 rd level, 11m above ground) POR3 Church, 2 Monk St., 25m to the West (5m above ground) POR4 House at 5 Monk St., 20m to the South (2 nd level, 5m above ground) (Distances are from closest edge of 852 Bank St. rooftop to the point of reception) 4. Methodology Used in Noise Impact Calculation The following sections describe the methodology and software used to model the sound pressure levels at the points of reception due to the noise sources while taking into account parameters such as source levels, distance, topography, barriers and building geometry. 4.1 Procedure Used to Assess Noise Impact at Each Point of Reception This environmental noise analysis was done using an environmental noise modeling software package called Cadna/A, which references ISO Cadna/A predicts environmental noise through calculations based on a 3D model which uses geometrical, landscape and topography data, combined with details of the proposed construction and the noise source power levels. We created a 3D rendering of the neighbourhood around 852 Bank St. and placed the noise sources with the manufacturer s sound power levels in the model (represented by the blue crosses). The colours on the ground and building represent the sound pressure level in that area. Sound power levels per octave band were entered into Cadna/A at the source s location and the resulting sound pressure levels were calculated at the points of reception.

REP N45 852 BANK ST. ENVIRONMENTAL NOISE STUDY Page 9 of 14 4.

9 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 9 of Other Parameters/Assumptions Used in Calculations The following chart describes the parameters used in the Cadna/A model: Parameter Value/Condition Ground Absorption Set to 0 for ground reflection Building Reflections Set to 2 orders of reflection Temperature ( C) 10 Relative Humidity (%) 70 Table 4.2 Parameters used in Cadna/A modeling. 5. Acoustic Assessment Summary This section summarizes the Cadna/A sound pressure level results for the model with and without noise mitigation measures. Section 5.1 below illustrates the steady state sound pressure levels generated by all the noise sources with no mitigation. Section 6 summarizes our noise mitigation recommendations and the resulting sound pressure levels. 5.1 Acoustic Assessment Summary for All Equipment with no Noise Mitigation The noise map in Figure 5.1 is like a temperature map showing hot zones and cool zones. Using the legend, it can be seen that for the worst-case scenario where the RTUs are at the edge of the roof, closest to PORs 1 &2, the PORs have SPLs in excess of the by-law limit of 50dBA. POR3 Church 51.9 dba SPL POR th Ave 60.6 dba SPL POR th Ave 57.7 dba SPL RTU 1-4 (91 dba SWL Each) POR4 House 51.4 dba SPL Figure Sound Pressure Levels (SPL) due to RTUs with no mitigation measures. (colours will display properly when this document is printed in colour or viewed on a computer)

10 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 10 of 14 Table 5.1 below summarizes the total calculated SPLs at the PORs. Worst-Case Scenario Sound Pressure Levels from RTU 1-4 at each POR POR1 (dba) POR2 (dba) POR3 (dba) POR4 (dba) Table 5.1 SPLs (dba) at the PORs with no noise mitigation With the RTUs located at the edge of the roof closest to PORs 1&2, the SPL at POR 1 & POR 2 is 60 dba. POR 3 and POR 4 have SPLs of 52 and 51 dba, respectively. These sound levels are well above by-law, thus noise mitigation solutions will be required for the RTUs. We present two noise reduction options in the following section. 6. Noise Control Measures and Recommendations In order to meet the by-law limit of 50 dba at each point of reception, we evaluated two noise mitigation solutions using our Cadna/A model. Each solution is discussed below and our preferred noise reduction method is indicated. Option 1: Select Quieter RTUs and Locate in Middle of Roof, Away from Building Edges (This is our primary recommendation) The simplest and most effective method to reduce the noise at the PORs is to select quieter mechanical equipment and to place it strategically on the roof. To do this, we moved the RTUs to the middle of the roof, away from the building edges and adjusted the sound power level of the units until the SPL at each POR was below 50 dba. We determined that the maximum allowable casing radiated SWL for each RTU is 81 dba. Figure 6.1 on the following page shows the new RTU locations and resulting noise levels at each POR.

11 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 11 of 14 POR3 Church 42.6 dba SPL POR th Ave 48.1 dba SPL POR th Ave 46.5 dba SPL POR4 House 45.7 dba SPL RTU 1-4 (81 dba SWL Each) Figure 6.1 SPLs at each POR using 81 dba SWL RTUs, located in the middle of the roof. (colours will display properly when this document is printed in colour or viewed on a computer) Using RTUs with a maximum SWL of 81 dba, located in the middle of the roof away from the building edges, we found that the SPLs at all PORs are below the noise by-law limit of 50dBA, with a safety factor of at least 2 dba. This is our primary recommendation. Table 6.1 below summarizes the sound pressure levels at each POR. Sound Pressure Levels at each POR with Option 1 Solution POR1 (dba) POR2 (dba) POR3 (dba) POR4 (dba) Table 6.1 SPLs (dba) at the PORs using RTUs with 81 dba SWL in the middle of the roof. Option 2: Use Current RTU Selection and Construct Barriers on Both Sides of Equipment If it is not possible to select quieter equipment and the current selection of RTUs must be used, then solid barriers with no gaps to the roof or along their length will need to be constructed on both sides of the mechanical equipment. Figure 6.2 on the following page illustrates the required barrier locations, with the RTUs located in the middle of the roof, as was done in Option 1.

REP N45 852 BANK ST. ENVIRONMENTAL NOISE STUDY Page 12 of 14 POR4 House 48.4 dba SPL POR3 Church 49.8 dba SPL Solid Barriers POR2 149 5 th Ave 51.2 dba SPL POR1 147 5 th Ave 50.

(colours will display properly when this document is printed in colour or viewed on a computer).

(dba) 50.2 51.2 49.8 48.4 Table 6.2 SPLs (dba) at the PORs using RTUs with 91 dba SWL in the middle of the roof, with concrete barriers on both sides of the equipment.

12 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 12 of 14 POR4 House 48.4 dba SPL POR3 Church 49.8 dba SPL Solid Barriers POR th Ave 51.2 dba SPL POR th Ave 50.2 dba SPL RTU 1-4 (91 dba SWL Each) Figure 6.2 SPLs at each POR using 91 dba SWL RTUs, located in the middle of the roof with solid barriers on either side of equipment. (colours will display properly when this document is printed in colour or viewed on a computer). Using solid barriers as show in the figure above, the sound pressure levels at each POR are as follows: Sound Pressure Levels at each POR with Option 2 Solution POR1 (dba) POR2 (dba) POR3 (dba) POR4 (dba) Table 6.2 SPLs (dba) at the PORs using RTUs with 91 dba SWL in the middle of the roof, with concrete barriers on both sides of the equipment. This solution will be costly and will still result in noise levels at or above the 50 dba by-law limit at PORs 1-3. We do not recommend this option if it can be avoided. If barriers are the preferred solution, they must be constructed in the following manner: Be minimum 2.0m tall (minimum 0.7m above the top of the RTUs) Be continuous from the top of the barrier to the bottom at the roof surface (no gaps either along the barrier or below the barrier) Have no gaps between barrier panels Have a surface density of at least 20kg/m 2. Rain drainage will have to be routed around the barriers and drains adjusted accordingly.

13 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 13 of Conclusion Using site plans and aerial maps as well as manufacturer sound power level data for the RTUs, we created a 3D acoustical model of the proposed commercial building at 852 Bank St. and calculated the sound pressure levels at the nearest residential buildings. Since the location of the mechanical equipment has not yet been decided, we examined the worst-case scenario where the RTUs are located at the edge of the roof closest to the points of reception. This worst-case scenario resulted in the highest noise levels of 58 and 61 dba SPL at PORs 1&2, which are well above the City of Ottawa By-Law Limit of 50 dba SPL. We therefore simulated two noise mitigation solutions to meet the by-law requirements, which are summarized below. Operating Scenario POR1 (dba) POR2 (dba) POR3 (dba) POR4 (dba) Worst-case Option Option Table 7.1 Summary of SPLs at each POR for worst-case scenario, Option 1 and Option 2. Option 1: Select Quieter RTUs and Locate in Middle of Roof, Away from Building Edges. Using quieter RTUs, each with an overall sound power level of 81 dba, and installing them in the middle of the roof will result in SPLs below 50 dba at the PORs, with a safety factor of at least 2 dba. This is the simplest and most cost-effective solution, and is our primary recommendation. Option 2: Use Current RTU Selection and Construct Barriers on Both Sides of Equipment. If it is not possible to select quieter equipment and the current selection of RTUs must be used, then concrete barriers will need to be constructed on both sides of the mechanical equipment. The barriers will need to be built according to the criteria on page 12. This is a very expensive solution and will still result in noise levels at or above the 50 dba by-law limit at PORs 1-3. We do not recommend proceeding with this option. If the recommendations in our primary noise mitigation solution, Option 1, are followed, the noise levels at the residential buildings closest to 852 Bank St. will meet the by-law limit. If you have any questions about our report, please do not hesitate to contact us. Sincerely, Peter Wright, M.Sc. Acoustic Consultant

14 REP N BANK ST. ENVIRONMENTAL NOISE STUDY Page 14 of 14 Appendix A Manufacturer Sound Power Level Data for RTUs

15 YTG-N-0912 ZH Physical Data Component Models ZH078 ZH090 ZH102 ZH120 ZH150 Nominal Tonnage AHRI COOLING PERFORMANCE Gross AHRI A point (Btu) AHRI net capacity (Btu) EER / / / SEER IEER / / / IPLV Nominal CFM System power (KW) Refrigerant type R-410A R-410A R-410A R-410A R-410A Refrigerant charge (lb-oz) System System AHRI HEATING PERFORMANCE Heating model Heat input (K Btu) Heat output (K Btu) AFUE % Steady state efficiency (%) No. burners No. stages Temperature Rise Range (ºF) Gas Limit Setting (ºF) Gas piping connection (in.) 3/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 3/4 DIMENSIONS (inches) Length /2 Width Height /4 50-3/4 50-3/4 OPERATING WT. (lbs.) COMPRESSORS Type Recip Recip Recip Scroll Scroll Quantity Unit Capacity Steps (%) 50 / / / / / 100 CONDENSER COIL DATA Face area (Sq. Ft.) Rows Fins per inch Tube diameter (in./mm) 1/25 1/25 1/25 1/25.71/18 2-pass Microchannel 2-pass Microchannel 2-pass Microchannel Circuitry Type 2-pass Microchannel 2-pass Microchannel EVAPORATOR COIL DATA Face area (Sq. Ft.) Rows Fins per inch Tube diameter Circuitry Type Intertwined Intertwined Intertwined Intertwined Intertwined Refrigerant control TXV TXV TXV TXV TXV 20 Johnson Controls Unitary Products

16 YTG-N-0912 Outdoor Sound Power Levels ZH/ZJ/ZR Size (Tons) 037 (3) 049 (4) 061 (5) 078 (6.5) 090 (7.5) 102 (8.5) 120 (10) 150 (12.5) 037 (3) 049 (4) 061 (5) 078 (6.5) 090 (7.5) 102 (8.5) 120 (10) 150 (12.5) 037 (3) 049 (4) 61 (5) 078 (6.5) 090 (7.5) 102 (8.5) 120 (10) 150 (12.5) Model Sound Rating 1 db (A) Octave Band Centerline Frequency (Hz) ZH ZH ZH ZH ZH ZH ZH ZH ZJ ZJ ZJ ZJ ZJ ZJ ZJ ZJ ZR ZR ZR ZR 83 ~ ZR 83 ~ ZR 83 ~ ZR 83 ~ ZR 84 ~ Rated in accordance with AHRI 270 standard. Johnson Controls Unitary Products 135

Environmental Noise Study of. Findlay Creek Public School Findlay Creek Drive, Ottawa, Ontario. R1. Prepared for: N45 Architecture Inc.

Environmental Noise Study of. Findlay Creek Public School Findlay Creek Drive, Ottawa, Ontario. R1. Prepared for: N45 Architecture Inc. Environmental Noise Study of Findlay Creek Public School 3010 Findlay Creek Drive, Ottawa, Ontario. R1 Prepared for: N45 Architecture Inc. Prepared by: Eric Sladic February 5 th, 2015 Contents 1.0 Introduction...1