You will need to have the Silverlight browser plugin installed in your machine. It is freely available from Microsoft. The calculators work on desktop computers only, not on mobile devices. Watch video
This U value and R value calculator carries out U and R value calculations for walls, roofs and ground floors and follows the method described in EN ISO 6946:2007 and EN ISO 13370:2007. Now in Imperial units and R value also
This psi value calculator will enable you to estimate the linear thermal transmittance (psi value) for the external wall – ground floor junction for different insulation thicknesses and thermal conductivities in accordance with BR497, with an accuracy of 0.01 W/mk without the need of thermal simulations.
This U value calculator carries out U value calculation of the centre of a glazing unit, and follows the method described in EN 673:2011. It does not calculate the U value for the whole window, including frame, glazing and spacer. This whole window U value calculator will be available very soon.
This Android app carries out U value calculation of the centre of a glazing unit, and it is very similar to the web version. This is our first Android app and it may need some improvements, so if you have any suggestions for new features or improvements, please let us know.