Acoustics case study

Alma Estate Regeneration Project

Background

The Alma Estate in Enfield, London is going through a 10-year regeneration programme. The works include demolition of existing buildings and construction of approximately 1,000 new homes including four tower blocks, a community centre and an energy centre.

Challenge

Noise and Vibration Assessment

SRL were initially commissioned to provide a noise and vibration assessment to support the Reserved Matters planning application. Noise on site was dominated by road traffic to the west and a railway line to the east. Enfield Council required a sound insulation strategy to mitigate both airborne and structure borne noise to protect the amenity of the future residents on the development.

Internal Acoustics – Community Centre 

One of the challenges surrounding the community centre was to reduce risk to the client and provide assurance to Building Control that noise from the use of the community centre (which included a music production studio) would not adversely affect residents in the apartments above

Building Services Noise

The development included a large Energy Centre. The Energy Centre was located in the ground floor of a residential block and produced relatively high levels of noise. Enfield Council set a planning condition which related to the control of noise from the energy centre at nearby noise sensitive receptors. This included an existing school which was within 20m of the Energy Centre.

Solution

Noise and Vibration Assessment

We used 3D noise modelling to predict noise propagation across the site at the different building levels and this enabled us to provide the optimum acoustic specifications for the external envelope, including glazing and ventilators, to achieve Enfield Council’s requirements for internal noise levels within dwellings.

Internal Acoustics – Community Centre 

We set noise limits in the community centre to maintain acceptable levels in the apartments above and placed responsibility to the operators to provide upgraded sound insulation if these noise limits were to be exceeded. This reduced the risk to the client of future noise complaints.

Building Services Noise

We worked very closely with the design team to specify appropriate noise and vibration control to reduce the Energy Centre’s impact on the nearby noise sensitive receptors. We specified acoustic louvres to the façade of the building, checked the proposed insertion loss performances of the attenuators to fresh air intakes and exhausts of air handling plant. We also gave advise to control vibration from plant to reduce structure borne noise within the building.

Our advice enabled the planning requirements which related to noise break out from the Energy Centre to the existing noise sensitive receptors to be achieved.