Posted: 13th October 2021
Getting things right from the earliest stages of your residential development can increase the likelihood of achieving planning consent for your development and reduce costs. Not considering noise from the outset may seem innocuous, but getting it wrong can result in project delays, bureaucratic headaches, and lower returns. Here’s how complying with ProPG Planning & Noise can help.
From sleep disturbance to feeling distracted or even annoyed, noise can be highly detrimental to the health of communities. Studies have repeatedly confirmed that noise can impact learning, reduce sleep quality, and have a negative impact on the mental health of both children and adults. In contrast, considerate noise management can have multiple beneficial impacts. The expectation of the listener is often a key component of this; the anticipated acoustic environment in a city centre flat will be different than that of a house in a rural village. It is usually unexpected, unwanted, or unnecessary noise that causes most problems. This is something that can be managed with a good acoustic design.
Launched in 2017, the Professional Practice Guidance on Planning and Noise (ProPG) is a collaborative document prepared by the Institute of Acoustics (IOA), Association of Noise Consultants (ANC), and the Chartered Institute of Environmental Health (CIEH). Its purpose is to “encourage better acoustic design for new residential development and aims to protect people from the harmful effects of noise.” The goal is not to increase costs or increase the complexity of planning. Rather, the agenda is to encourage careful, thoughtful, and future-orientated design. The document is intended to align with government policies set out in the National Planning Policy Framework (NPPF) and the Noise Policy Statement for England (NPSE).
ProPG is split into two stages. At Stage 1 a sound level survey is conducted to determine the existing noise climate over a “typical worst-case” 24-hour period. This may require sound levels to be measured over several days, to ensure that the typical worst-case levels have been captured. If necessary, the measured sound levels can be combined with anticipated changes to the acoustic environment, for example, if a large housing development would result in increased traffic flows in the area.
Measured or calculated levels are compared against a graph in the document to establish the potential effect of noise on future residents if no noise mitigation measures are incorporated into the design.
It is noticeable that there aren’t firm boundaries between the different subjective descriptions. ProPG explains that the numerical values shown are indicative only and should be “interpreted flexibly having regard to the locality, the project and the wider context.” This links back to the earlier discussion about the expectation of the listener. Traditionally people living near a main road may have to keep windows closed at busy times or at night because of the noise, whereas the most desirable rooms in a beachfront hotel are often those overlooking the sea with the sound of waves on the beach – even if the measured decibel level were the same in both locations.
Once the potential noise risk has been identified, then following a good acoustic design process forms part of achieving good design, as required by the NPPF and NPSE. The aim is not to overdesign or “gold plate” all new developments, but to ensure the optimum acoustic conditions for each individual site, taking into account the potential adverse noise risk identified at Stage 1.
In the past, noise was often only considered to inside proposed new residential dwellings with the acoustic specification of façade elements designed accordingly. For some developments, this resulted in sealed boxes where residents had to choose between unacceptable noise levels when opening their windows for cooling or having to keep windows closed. The aim of a good acoustic design process is to have a holistic approach to the design. This could include attenuating the sound prior to getting to a dwelling (e.g., using barriers or screening one building with another), the orientation of buildings or of sensitive rooms within a dwelling (for example, having bathrooms or kitchens on the noisier façade and keeping bedrooms or living rooms to the rear), or considering noise to outside amenity areas. The acoustic performance of windows and other elements of the façade, whilst still a key aspect, should be considered as the last line of defence once all other appropriate measures have been taken.
The World Health Organisation (WHO) describes unwanted noise as an “important environmental problem.” The WHO also describes noise as being a particularly difficult problem to solve. For developers, considering ProPG Planning & Noise from the earliest stage of your development increases the likelihood of projects being given the green light, especially when the concepts are infused in the design from the start.
ProPG Planning & Noise offers exciting opportunities for planners and developers, especially during an era where the government is encouraging more design flexibility. To learn more about giving your project a quiet yet competitive edge, please get in touch with one of our acoustic consultants today.
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