U value and R value calculator

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.

Click here for an alternative version that works in most browsers and devices.

External full fill cavity wall – ground floor. Insulation below slab. Psi value calculator

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.

Whole window U value calculator (web version)

This U value calculator carries out whole window  and centre of the glazing unit U value calculations, and follows the method described in EN ISO 10077- 1:2006 and EN 673:2011. It calculates the U value for the whole window, including frame, glazing and spacer.

U value glazing calculator (Android version)

Android app on Google Play

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.