Projects

Example Reports


NOISE SURVEY OF PROPOSED PLACE OF WORSHIP


Scope of Report

To measure exterior noise levels at the site of a proposed place of worship and to comment upon the expected noise impact to local residents.

1. INTRODUCTION

1.1 The ... requires to relocate their place of worship due to an expanding congregation and a desire to expand the range of community services provided.

1.2 ... is a commercial building that the see fit for their purposes.

1.3 Planning permission has been refused for this re-location. Expected adverse noise impact has been cited as one of the reasons for refusal.

1.4 Civil Engineering Dynamics were instructed by the to perform a noise survey of a trial service at and to provide a report that comments upon the expected noise impact to local residents. The report forms part of a planning appeal.

2. THE SITE

2.1 ... is a three storey commercial building on the eastern side of ...,. We are informed, by the client, the building has been unoccupied for the past eleven years. All the windows of are metal double glazed thermal units.

2.2 The western side of contains small, two-storey houses. Most houses have single glazed windows.

2.3 ... is bounded by a storage warehouse to the south, and another unoccupied commercial building to the north.

2.4 ... is a narrow road that joins the ... to the north, the ... Road to the south, and ... Road to the west. ... Road is a similar residential / light commercial road to ... Road. The ... and ... are both busy main roads.

2.5 The site is approximately half a mile to the north the ... central main shopping areas.

3. MEASUREMENT PROCEDURE

3.1 The survey was undertaken from 10:30 to 15:00 on Sunday 13th August 00. The weather was dry and calm.

3.2 A Bruel & Kjaer 2236E Sound Level Meter was set-up at the boundary wall to the nearest residence to ... House. This is approximately 1m from the façade of Road and is directly opposite ... House.

3.3 The sound level meter logged 10-minute LAeq and L90.

3.4 An engineer was in attendance throughout the survey to observe events and to provide subjective observations of the noise environment.

4. RESULTS

4.1 Logged noise results are shown in Figure 1.

4.2 The service started at 11:00. Most of the congregation had left the site by around 13:30.

4.3 Table 1 shows typical subjective responses to changes in noise levels.

Table 1: Typical Subjective Responses To Changes In Noise Levels

Change in Noise Level (dB)
+/- 3 dB
+/- 5 dB
+/- 10 dB
Typical Subjective Response
Just noticeable difference
Clearly perceptible difference
Twice or half as loud

4.4 From the measured levels alone, it appears that the service is increasing the noise levels in ... Road, and to a clearly noticeable extent at some times. However, this is misleading. It is vital to consider all of the activities occurring in ... Road throughout the measurement period.

4.5 Impact of Internal Noise Sources

4.5.1 The service was held on the top (second) floor of ... House.

4.5.2 The service uses a PA system to address the congregation and to amplify a keyboard and choir. A drumkit is also used in the service. Our engineer didn't hear any amplified aspect of the service after around 12:30.

4.5.3 The air-conditioning of House was not operational on the day of the service. This meant that some windows were open during the service, which would not normally occur.

4.5.4 PPG 24 'Planning and Noise' suggests that the sound insulation of an open window, regardless of type, is around 10 - 15 dB.

4.5.5 Pilkington's 'Glass and Noise Control - Technical Bulletin' states that for 4/12/4 thermal double glazing (the lowest specification glazing unit in their range), a sound reduction of around 30 dB can be expected.

4.5.6 Therefore, we would expect the impact of internal noise sources to be 15 - 20 dB lower than those measured in this survey, when the service is undertaken in normal circumstances (i.e. air conditioning working, all windows closed).

4.5.7 This will lower noise levels from the amplified service below the background noise levels in Union Road, and is not expected to be perceptible.

4.5.8 Therefore, we expect that there will be no impact to the local noise environment from internal noise sources under normal operating conditions. That is, with all the windows closed.

4.6 Impact of External Noise Sources Related to the Service

4.6.1 The main source of potential noise impact is that generated by increased traffic on Road due to the congregation arriving and leaving.

4.6.2 On the day of the survey, the congregation used a small car-park in Road.

4.6.3 Because this was a 'one-off' test, many of the congregation had to stop their cars outside to ask directions from the assistants.

4.6.4 The noise of cars idling has inevitably increased the noise impact of this source by an unquantifiable amount over what would normally occur - i.e. the congregation driving directly to the car park and approaching House on foot.

4.6.5 Again, because this was a test service, the PA equipment was unloaded and loaded into a minibus outside House. This would not occur if the building was the regular place of worship.

4.7 Impact of External Noise Sources Unrelated to the Service

4.7.1 A number of events occurred during the survey that have increased the noise levels, but were unrelated to the noise of the service and so must be taken into account when examining Figure 1.

4.7.2 Around 13:00, a child was leaning out of a front upstairs window, approximately 20m from the measurement location, impersonating a barking dog. This is the most probable explanation for the high levels measured at this time.

4.7.3 From around 13:10 to 13:40, music was emanating from the front upstairs window of ... Road. This will have increased the noise levels during this time.

4.7.4 From around 13:45 to 14:00, our engineer was engaged in conversation by a resident of directly adjacent to the sound level meter. For reasons of manners and public relations, our engineer chose not to suggest that the resident cease speaking, or move to another location. The high levels at this time can be attributed to this and should be disregarded from the assessment.

5. CONCLUSIONS

5.1 It is inevitable that the residents of will perceive an adverse noise impact following any use of ..., as it has remained unoccupied for some eleven years.

5.2 What distinguishes this proposed use from typical commercial use is the use of the building on a Sunday morning. However it is noted that the service does not start until 11:00, and we are informed that the congregation do not arrive en masse, preferring to arrive typically anytime between 10:30 and 11:30. This was observed during this survey.

5.3 Traffic noise from the two nearby main roads and aeroplane pass-by's contribute to the existing noise environment. Therefore, we would expect the impact of increased traffic on Road to be less significant than most residential areas.

5.4 We expect that there will be no impact to the noise environment of Road from internal noise sources in House, provided that all of the windows are fully closed at all times.

5.5 We expect that there will be an adverse impact to the noise environment between 10:30 and 11:30 due to increased traffic on Road. However, this impact will be lessened by the spread of arrival times, and is expected to be less than that measured in this survey because the location of the car park will be known to the congregation.

5.6 We would expect that the impact due to increased traffic may be around 3 dB between 10:30 and 11:30. This is not a significant increase and, considering the time of the day and location, not expected to be a nuisance to most people.