Bloom, Farringdon
Project summary
Bloom is an 8-storey building housing 145,000 sq ft of work, retail and amenity spaces, located directly above the new Farringdon Elizabeth line station. The acoustic design had to carefully consider the existing and new underground railway lines below the site, as well as the ventilation plant serving the Elizabeth line. The project achieved BREEAM Outstanding and WELL Platinum certification.
Sandy Brown was appointed to provide advice for the development of Bloom. Important considerations were:
- noise ingress to noise sensitive spaces and building envelope design
- noise transfer from the existing London Underground and Thameslink railway lines below the site
- noise transfer from the, then in construction, Elizabeth line station and tunnel ventilation system below and adjacent to the site
- internal sound insulation of walls, floors and doors
- acoustic finishes in the entrance foyer
- acoustic finishes in open plan office spaces
- control of sound transmission to and from retail areas
- acoustic assessment and design of internal building services systems
- acoustic assessment and design of external building services plant items
- control of sound transmission from plant rooms to office spaces.
Detailed design
The key initial consideration was the noise and vibration transfer from the existing London Underground and Thameslink lines, and the, then in construction, Elizabeth line station and tunnel ventilation system. A ground-borne vibration survey was carried out at the early stages to assess the potential re-radiated noise levels, from the existing railway lines, within the proposed scheme.
A review of the Elizabeth line technical design was carried out to assess the potential risk of noise and vibration transfer from the proposed tunnel ventilation systems. The findings from this review enabled suitable enhancements to be incorporated within the architectural design.
As the building is located on a busy city centre road, ensuring suitable internal noise levels on the office floors could be achieved was a key part of the design. 3D environmental noise modelling was carried out to assess the required facade sound insulation performance.
