U-Values describe the thermal transmittance that takes place through a structure. U-Values are required when establishing potential construction build ups and they are fundamental to sustainable design, energy efficiency and compliance.

A U-Value (W/m2K) is simply the rate of heat transfer through a structure divided by the difference in temperature across that structure.

SRE’s energy consultants use specialist software (Build Desk & Therm) to calculate U-Values in accordance with the national conventions (BR443) for both Part L compliance in SAP/SBEM as well as part of wider modelling for PSI value calculations and condensation risk assessments. These calculations are assessed in the broader context of the building performance including thermal mass, overheating and material selection and sustainable procurement.

The lower the U-Value the higher the thermal performance of the structure and SRE is continually updating our knowledge and assessment of new and innovative products that reduce the U-Value.