Wood effect secondary glazing at Braintree Town Hall

Wood effect secondary glazing


Project Profile


thermal secondary glazing, sustainability, coloured and wood grain finishes

Braintree Town Hall is a Grade II* Listed building. The original, large, Georgian style sash windows with their ageing, single glazed panes, provide little insulation. The Council recognised that these beautiful period features needed upgrading and so approached Selectaglaze to come up with a treatment sympathetic to the building. The Council's original request was for timber framed secondary glazing, so when Selectaglaze proposed aluminium frames coated with a wood effect, both they and the Conservation Officer were sceptical. However, when the Technical Advisor placed a sample frame within the primary window prior to his meeting with local officials, it blended so well with the beautiful timber panelled interior he had to draw their attention to it. Thermographic imaging image The wood effect aluminium secondary glazing sample blended so well with the interior, that the proposed treatment was accepted by both the client and the Conservation Officer. A total of 20 bespoke oak wood-grain secondary glazing units were manufactured. The Series 20 range was specified for their slimline profiles which have been designed to blend into period properties. Series 25 was specified for the large sashes, as their studier frames are designed to take heavier glass, whilst the unit retains its unobtrusive properties. Each frame was glazed with 4mm toughened low-E glass to ensure that a U-value of 1.9 would be achieved throughout the installation. Heat imaging photography taken before and after the treatment shows the dramatic change in performance of the primary windows treated. “The estimated savings from installing secondary glazing in the Town Hall is at least 12% of the combined heating bill, over £400pa at current prices, which are predicted to increase annually.” Councillor Robert Mitchell, Deputy Cabinet Member for Environment and Place. This successful wood effect secondary glazing treatment has resulted in Council Offices that are now warm, comfortable and seen a noticeable reduction in noise ingress. The Council have already been able to demonstrate a dramatic reduction in their heating bills. This successful treatment of a Grade II* building has dramatically reduced its carbon footprint for future generations to come.