Panorama St Pauls, 81 Newgate Street

Background 

The transformation of 81 Newgate Street is set to turn the former BT headquarters built in the 1980s into a modern 13-storey workplace with large open plan office floors, new terrace areas across all levels, retail units at low level, a gym, swimming pool a rooftop terrace and upgraded building services.

Anderson Acoustics was appointed  by  Chapman BDSP  and later by  MACE  on behalf of  NG  Devco  to  provide  end to end  acoustic consultancy, for the shell and core element of the scheme, ensuring the development met strict planning, BREEAM Outstanding (offices)/Excellent (retail), and WELL Platinum requirements, as well as discharging two acoustics-related planning conditions.

The Challenge 

With its central City of London location, the project faced three major acoustic challenges: 

• A  high noise  environment dominated by major roads and nearby commercial plant, but also surrounded by some residential uses (surprising but present in the heart of London); 
• Multiple new  noise sensitive  features, including private terraces and a public rooftop amenity space; which also deserved acoustic considerations when addressing noise impacts from proposed plant;
• Strict planning conditions  requiring both day-to-day and emergency plant noise to sit 10 dB below background levels, plus demanding  internal  comfort  and sound insulation standards between adjacent commercial/retail and office uses.  Day-to-day plant was mainly distributed across basements, a  double height  plant room at levels 12–13, and external roof areas. A life safety generator was located at 1st floor level (adjacent to office areas), along with several smoke extract fans at roof level. Noise from neighbouring commercial buildings also affected baseline conditions, complicating acoustic commissioning testing at the end of the project and requiring a  context sensitive  approach when assessing noise impact on nearby receptors.  

The project  also  targeted both  BREEAM Outstanding (offices) and Excellent (retail) and  WELL Platinum, requiring: 

• Clearly defined acoustic zones and high  sound insulation targets between  adjacent “loud” and “sensitive” areas (e.g., emergency generator next to office space);
• Control of reverberation in open plan offices, atria, circulation spaces, retail street at ground floor; 
• Protection of speech privacy; 
• Compliance with internal ambient noise levels across varied uses (office floors, gym, retail, lobby) 

The goal was to protect neighbouring commercial and residential receptors and create an excellent acoustic environment for future occupants of the building. 

What We Did 

Our team delivered a full suite of acoustic services across design, construction, and commissioning stages: 

• 3D noise modelling  to assess terrace noise, plant emissions, and façade sound insulation performance. We developed detailed models incorporating: 

• • Geometry of new massing and terraces; 
  • Screening effects from roof structures, balustrades and plant enclosures; 
  • Daytime and nighttime operating plant scenarios; 
  • Human voice sources across terraces (normal, raised, loud); 
  • Worst case occupancy assumptions for public and office terrace areas; 
  • Propagation paths to all residential and office receptors 

• Onsite testing, including plant measurements, airborne sound insulation tests, and terrace impact assessments were used to discharge the relevant planning conditions; 
• Baseline noise monitoring to understand existing environmental conditions;  
• Design guidance  covering internal noise criteria, partition performance, reverberation control, and ventilation noise in office areas. We  provided  detailed design guidance on: 

• • Partition construction and detailing; 
  • Internal background noise limits; 
  • Reverberation control; 
  • Floor/ceiling buildups to control impact noise; 
  • Acoustic zoning and sound mapping 

• Support for BREEAM and WELL, helping secure targeted acoustic credits 

The Result 

Our work enabled 81 Newgate Street to achieve: 

• Full compliance with all City of London acoustic-related planning conditions; 
• Verified BREEAM Pol 05 and Hea 05 performance.  The detailed assessments and measured results confirmed: 

• • Plant noise emissions are  below required thresholds; 
  • External façades and glazing solutions achieve required internal noise levels; 
  • Report evidence secured credits for both office and retail elements 

• Support for WELL v2 Platinum ambitions.  The project achieved or  maintained  eligibility for: 

• • S01 – Sound Mapping; 
  • S02 – Limit Backgound Noise Levels;
  • S03 – Sound Barriers; 
  • S06 – Minimum Background Sound (potential) 

• Neighbour friendly  terraces, with modelling confirming negligible impact on residential receptors; 
• A comfortable and  high performing  acoustic environment  for future building occupants.

Project Progress 

Practical completion was achieved last year.  This is one of the largest redevelopments to ever achieve planning in the City of London.  

For more information, head on over to the Mace Group  website