U Value Calculations are used to quantify the heat transfer through a thermal element of a building (floors, walls, roofs). The amount of heat transfer depends on the thickness and thermal conductivity of each building material in a given cross-section of the thermal envelope. 

Part L contains limiting U Value thresholds for all floors, walls, roofs, windows and doors. Low U Values are essential for all domestic projects to meet the Target Fabric Energy Efficiency (TFEE) threshold outlined under Part L1A 2013. The TER notional dwelling calculation against which all completed Part L1A calculations are compared against within the SAP software uses the following U Value figures in its assessment:

External Walls   -    0.18 W/m2K
Floor   -   0.13 W/m2K
Party Walls   -   0.00 W/m2K
Roof   -   0.13 W/m2K
Windows   -   1.40 W/m2K
Doors (solid)   -   1.00 W/m2K

Get in touch:

Our team are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

 

 

 

Get in touch:

Our team are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 
0333 5777 577 or fill in our contact form and we will get back to you.

CASE STUDIES

BLOG: How to achieve a good U Value 

Top Tips:

  • Use the TER notional dwelling U Value thresholds as a guide when designing a building rather than the limiting U Value thresholds.
  • Consider whether the insulation being used has calculated psi values that can be incorporated in the SAP Calculation.