Refurbishment and thermal improvement of glazed facades to Crescent House wins planning and listed building consent.

Studio Partington worked closely with Golden Lane Estate residents, Historic England, 20th Century Society, City of London planners and other stakeholders on the proposals to ensure that a favourable balance is struck between improving energy performance and retaining historic fabric and the original design intension of Chamberlin, Powell and Bon. The proposals, which also include additional insulation to the roofs, soffits, new demand-controlled ventilation, and starting a move to low carbon heating system are predicted to reduce heating demand by 50-60% per home.

VIG is a relatively new technology where two 4 mm sheets of glass are bonded together with a 0.3 mm vacuum created between to the two sheets of glass, resulting in a typical centre pane U-value of 0.5 W/m2K (compared to 1.2 for traditional double-glazed unit, or 0.7 for a typical triple glazed unit). While providing a significant improvement over the existing single glazing, the glass can be accommodated into the existing sapele timber frames with minimal adaption or loss of historic fabric.

Crescent House Pilot Project

A Pilot Project has been run in a vacant home within Crescent House to enable a detailed assessment of the proposals in both heritage and performance terms. Working with the BRE, baseline measurements of existing overall airtightness, a smoke survey to highlight areas of air leakage, weathertightness (spray bar and hose pipe testing), a week long acoustic survey, and a thermographic survey to highlight areas of heat loss where undertaken. A full package of improvement works was then carried out: removing the existing single glazing, repairing the existing window frames, installing new VIG, adding insulation in strategic locations on the facade, installing the demand-controlled ventilation system, and new all-electric heating and hot water systems.

With all works complete the same set of tests were carried out to measure improvements. The works were found to have significantly improved the airtightness of the home to 4.8 m3/m2/hr @ 50 Pa, made a 50% improvement in the acoustic insulation provided by the façade, and reduced water ingress.

Over a series of open days, GLE residents, 20th Century Society, Historic England, City of London planners, City of London Conservation Area Advisory Committee, and Barbican and Golden Lane Neighbourhood Forum were all able to view the installed works, allowing for an appraisal of the proposal against the existing windows in surrounding homes.

A three-month post-occupancy monitoring project is now underway to provide "lived-in" data on the reduction in heating load, the efficiency of the new demand-controlled ventilation system (by measuring relative humidity levels in the home), and detailed monitoring of the dew point of the existing metal framed window.

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Crescent House unanimous approval at planning committee