Thermal Transmittance U vs Th. Resistance R

To achieve thermal comfort and energy efficiency in buildings, a primary role is played by the thermal envelope: this is required to thermally decouple the indoor environment from the ever-changing external conditions, both in summer and in winter. The structures of the thermal envelope need to be able to control the amount of heat migrating through them: the thermal resistance and the thermal transmittance are two ways to describe this phenomenon.

Insulation materials: discovering the lambda value

The lambda value of a material indicates its ability to transfer heat: this property is therefore very important in the design of highly performing buildings and passive houses. The information commonly available is unfortunately quite confusing: with this article, we'll try and shed some light on the topic.