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TYPICAL U-VALUE CALCULATIONS (REFURBISHMENT) We have detailed a number of non-traditional house types in this section, along with three traditional brick / blockwork build methods. The U-values given on this page have been summarised and are strictly for guidance purposes only. To receive a comprehensive U-Value Calculation, including Condensation Risk Analysis and Temperature Profiles, please contact WBS Technical Support on 08458 382380 or visit the U-Value Calculations page of our Technical Support section. We regret that we can only offer FREE U-Value Calculations for External Wall projects.

FEATURED CONSTRUCTION TYPES Blockwork with Cavity Laing Easiform Brickwork with Cavity Orlit 225mm Solid Brickwork Reema Airey Newland Tarran BISF (Upper Floor) Unity Boswell Wates Cornish Wimpey No Fines Kenkast Woolaway Blockwork with Cavity Uninsulated U-Value: 0.957 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 50mm Polyisocyanurate (PIR) 0.340 W/m²K 50mm Phenolic 0.282 W/m²K View Example Calculations Brickwork with Cavity Uninsulated U-Value: 1.382 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 80mm Mineral Wool 0.330 W/m²K 50mm Phenolic 0.313 W/m²K View Example Calculations 225mm Solid Brickwork Uninsulated U-Value: 2.033 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 70mm Polyisocyanurate (PIR) 0.325 W/m²K 60mm Phenolic 0.291 W/m²K View Example Calculations Airey Uninsulated U-Value: 0.948 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 60mm Expanded Polystyrene 0.321 W/m²K 40mm Phenolic 0.314 W/m²K View Example Calculations BISF (Upper Floor) Uninsulated U-Value: 1.600 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 80mm Expanded Polystyrene 0.327 W/m²K 50mm Phenolic 0.311 W/m²K View Example Calculations Boswell Uninsulated U-Value: 1.916 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Expanded Polystyrene 0.322 W/m²K 50mm Phenolic 0.334 W/m²K View Example Calculations Cornish Uninsulated U-Value: 2.041 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Mineral Wool 0.325 W/m²K 50mm PIR 0.338 W/m²K View Example Calculations Kenkast Uninsulated U-Value: 2.525 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Mineral Wool 0.335 W/m²K 60mm Phenolic 0.229 W/m²K View Example Calculations Laing Easiform Uninsulated U-Value: 1.938 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 70mm Polyisocyanurate (PIR) 0.322 W/m²K 50mm Phenolic 0.335 W/m²K View Example Calculations Orlit Uninsulated U-Value: 1.339 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 60mm Polyisocyanurate (PIR) 0.336 W/m²K 50mm Phenolic 0.327 W/m²K View Example Calculations Reema Uninsulated U-Value: 2.375 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Expanded Polystyrene 0.332 W/m²K 60mm Phenolic 0.297 W/m²K View Example Calculations Newland Tarran Uninsulated U-Value: 2.232 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 70mm Polyisocyanurate (PIR) 0.329 W/m²K 60mm Phenolic 0.295 W/m²K View Example Calculations Unity Uninsulated U-Value: 2.060 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Mineral Wool 0.325 W/m²K 50mm Phenolic 0.339 W/m²K View Example Calculations Wates Uninsulated U-Value: 0.330W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 40mm Expanded Polystyrene 0.239 W/m²K 30mm PIR 0.237 W/m²K View Example Calculations Wimpey No Fines Uninsulated U-Value: 2.494 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 70mm Polyisocyanurate (PIR) 0.3235 W/m²K 50mm Phenolic 0.349 W/m²K View Example Calculations Woolaway Uninsulated U-Value: 2.016 W/m²K   Insulation Type 1 U Value 1 Insulation Type 2 U Value 2 90mm Expanded Polystyrene 0.324 W/m²K 50mm Phenolic 0.337 W/m²K View Example Calculations NB: Insulant 'K' Values have been based on the following: INSULANT THICKNESS W/m²K EPS 10mm - 160mm 0.036 - 0.038 PIR 0mm - 79mm 0.028 PIR 80mm - 119mm 0.027 Mineral Wool 20mm - 180mm 0.036 Phenolic 25mm - 44mm 0.023 Phenolic 45mm - 120mm 0.021