George Barnsdale can produce BFRC approved thermal simulations in house. This means thermal performance is designed into all windows.
High thermal performance of timber windows has a great effect on long term energy costs.
Barnsdale windows are designed to achieve the best performance without the need to use expensive and unattractive triple glazed units.
When considering thermal performance a number of factors need to be taken into account, such as the overall heat loss of the window (U-Value). A very low u-value will reduce heat loss and may be a better figure to consider than the overall energy rating. For example, on the North Side of the building or if sunlight is likely to cause too much thermal gain.
Solar gain can give windows an overall positive thermal performance. Our test window shows a positive figure of 1kWh/m2/year. Larger windows with fewer glazing bars can achieve even greater gains, but as mentioned above, this can be counter productive.
Air leakage has traditionally been considered a problem with timber windows, but all George Barnsdale windows perform exceptionally well, therefore little thought needs to be given to this.