Background
Xenia Developments Ltd commissioned Anderson Acoustics Limited to provide acoustic consultancy for the refurbishment of a four-storey, listed building at 196 & 197 Parrock Street, Gravesend. The property, previously used as offices, was being converted into a house in multiple occupation (HMO) with a self-contained flat and nine dwellings with en-suites and shared kitchens.
Challenge
The main challenge was to ensure that the new residential accommodation met stringent internal ambient noise level guidelines (BS8233:2014) and sound insulation standards (Approved Document E of the Building Regulations). The building’s location on a busy road (A226 Parrock Street) exposed it to significant traffic noise, and as a listed property, there were restrictions on altering the façade and windows. Initial surveys revealed that the existing façade did not provide adequate sound reduction, and the separating floors between rooms also failed to meet regulatory standards.
What We Did
- Comprehensive Noise Survey: Conducted detailed environmental noise monitoring both externally (at the façade) and internally (within rooms), including both unattended and attended measurements;
- Assessment & Modelling: Analysed the sound reduction performance of the existing building fabric and separating elements, referencing BS8233:2014 and WHO guidelines;
- Façade Upgrade Recommendations: Proposed secondary glazing for the front elevation to improve sound insulation, as full window replacement was likely restricted due to the building’s listed status;
- Internal Sound Insulation Solutions: Recommended upgrades to separating floors and walls, including:
-
- Installation of floating floors and resilient layers to control impact noise;
- Additional ceiling build-ups with dense plasterboard and mineral wool insulation;
- Enhanced wall linings and sealing of former door openings to improve airborne sound insulation.
- Ventilation Advice: Suggested mechanical ventilation systems to maintain air quality without compromising acoustic performance, given the limitations on passive ventilation in a listed building.
Result
The acoustic design solutions ensured that the refurbished dwellings would comply with BS8233:2014 for internal noise levels and Approved Document E for sound insulation. The recommended upgrades to glazing and internal structures addressed both regulatory requirements and the unique constraints of working with a listed building. As a result, future residents will benefit from a comfortable, quiet living environment, and the development met all necessary planning and building control standards
Project Progress
Gravesham Borough Council granted Listed Building consent for the conversion of the existing building on 7th February 2025.
