Background
Galliard (Gravesend) Limited sought to redevelop the former St Joseph’s Convent Preparatory School site in Gravesend, Kent. The proposed scheme included 54 new residential dwellings, associated parking, green space, and a new general practitioner (GP) clinic.
Given the site’s proximity to busy roads and other noise sources, a comprehensive noise impact assessment was required to support the planning application and ensure a high standard of living for future residents.
Challenge
The primary challenge was to assess and mitigate the impact of environmental noise – mainly from road traffic on Old Road East – on the proposed development. The site’s northern boundary, in particular, was exposed to high noise levels, raising concerns about compliance with national and local noise standards.
Additionally, it was necessary to ensure that noise generated by the new development would not adversely affect existing nearby noise-sensitive receptors (NSRs), such as neighbouring homes and community facilities.
What we Did
Detailed Noise Survey and Modelling
We conducted continuous unattended noise surveys at multiple locations around the site to capture representative data. The dominant noise source was identified as road traffic, with occasional contributions from aircraft and local activity. Using this data, a 3D environmental noise model was developed to predict noise levels across the site and inform mitigation strategies.
Compliance with Guidance and Standards
The assessment followed the Professional Practice Guidance on Planning & Noise (ProPG), British Standard BS 8233, and local planning policies. The process included:
- Stage 1: Initial noise risk assessment, which identified the northern boundary as “high risk” for noise exposure;
- Stage 2: Full assessment, including good acoustic design practices, internal noise level guidelines, and external amenity area assessments.
Mitigation Strategies
- Façade Zoning: The site was divided into zones based on predicted noise exposure. Higher-specification glazing and acoustic ventilators were specified for dwellings facing Old Road East;
- Alternative Cooling Solutions: For the most exposed bedrooms, alternative ventilative cooling (e.g., mechanical systems) was recommended to avoid the need for open windows at night, which could compromise internal noise levels;
- Amenity Space Design: It was argued that higher noise levels found on some private balconies were offset by the communal green space within the design, ensuring residents had access to quieter outdoor areas;
- Assessment of Development-Generated Noise: The impact of additional traffic and building services was modelled, with recommendations for plant noise limits and boundary treatments (e.g., solid timber fencing) to protect neighbouring properties.
Conclusion
The assessment demonstrated that, with the recommended mitigation measures, the development could achieve compliance with relevant noise standards. Key outcomes included:
- Internal noise levels within dwellings would meet BS 8233 guidelines, provided the specified glazing and ventilation were installed;
- Most outdoor amenity areas would offer acceptable noise environments, with communal green space compensating for any localised exceedances;
- The increase in noise at nearby sensitive receptors due to the development was found to be negligible, falling within the “No Observed Adverse Effect Level” category;
- The assessment concluded that, subject to the implementation of the proposed measures, planning consent should be granted for the scheme.
Project Progress
Gravesham Borough Council granted permission for the land to be developed on 21st November 2025.
