R-value (Thermal Resistance)2019-10-29T16:38:50+00:00

Thermal resistance (or R-value) is a heat property and a measurement of a temperature difference by which an object or material resists a heat flow. Thermal resistance is the reciprocal of thermal conductance.

U-value (Thermal Transmittance)2019-10-29T18:14:15+00:00

U-value measures how effective a material is as an insulator. The lower the U-value is, the better the material is as a heat insulator.

When we talk about the U-Value of a particular component of a building such as a wall, roof or window, we’re describing how well or how badly that component transmits heat from the inside (usually) to the outside. On a cold day in the UK when we’re warm and cosy on the inside of the building, we will be happier the lower the U-Value is – because it means that our wall or roof or window is quite good at holding-up the heat getting to the outside.

This is a great video that explains U-value:

Our friends over at Eco Merchant have compiled a really good explanation of the insulation properties, you can read it here: