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Environmental Benefits of Double Glazed Timber Sash Windows 


With carbon emissions on the rise across the world, the ever-increasing need to be environmentally friendly also applies to period properties, many of which have timber sash windows with single-glazing. If you are thinking about replacing or improving your traditional timber sash windows, now could be the time, as environmental concerns are growing across the UK and the introduction in the new Green Deal


The Department of Energy and Climate Change stated that ‘in 2016, UK net emissions of carbon dioxide were provisionally estimated to be 479.1 million tonnes (Mt) […] increasing on the previous year by 4.5%, (DECC, 2013). The typical traditional home will lose about 10% of its heat through windows and 15% through draughts.


When measuring thermal efficiency, timber sash windows are measured by their “U-Value”, with 'single-glazed timber-framed windows having a U-Value as low as 5.5, with double-glazed windows having a rating of 2, over half the loss. Did you know that ‘Replacing your old timber windows with new double-glazed timber sash windows can reduce heat loss by half, save around £175 a year on fuel bills, and around 720kg CO2 a year.


Barnsbury Joinery specialises in manufacturing and installing double-glazed Slimline units. These have a 7mm perimeter seal depth, and can be glazed into most single glazed period sash windows, giving a U-value of only 1.9, meaning your timber sash windows can now be A-grade energy efficient. When clients think about updating properties located in Conservation areas, owners often find the replacement of timber sash windows the easiest step to reduce heat loss, thus CO2 emissions, popular because loose-fitting frames with cold glass are often a very telling reminder of heating loss within a property.


In addition to the energy efficient double-glazed Slimline units, Barnsbury Joinery has also perfected a process called E-Seal, a sensitive process of introducing delicate fibre and pressure seals into the working areas of timber sash windows. These gaps, if left unfilled, can cause dirt and dust ingress, draughts and heat loss, but with E-Seal, sash windows can be made more environmentally friendly without changing the appearance of the window. Because the process is sensitive and discrete, conservation approval from local authorities is easy to obtain and many conservation groups welcome this product as an alternative to uPVC windows.


To save time at Barnsbury Joinery we have implemented an online quote request system. Once we receive your request we will endeavour to contact you within 24 hours. If you require assistance or would like to discuss your requirements, please do not hesitate to contact us directly on 0207-1646305


At Barnsbury Joinery we service all of London and surrounding areas. Including Islington, Hackney, Hampstead, Primrose Hill, Camden, Stoke Newington, Clapham, Angel, Canonbury, De Beauvoir Town and Clerkenwell. Please call us now to find out if we work in your local area.

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