Pultec has launched the 5000 Series range of windows which can provide whole window U-values of 0.7W/m2K

The windows are manufactured from a composite material - pultruded fibre reinforced polymer - which possesses very low thermal conductance, similar to glass itself. The company claims the frames have twice the strength-to-weight ratio of steel and since they are unaffected by the elements, they have a 50 to 75-year service life, 25-year guarantee and require no maintenance.

The windows are available in any colour and can help gain credits under the Code for Sustainable Homes.