Validation of RdSAP U-calculation methodology for traditional stone walls

Description

The Scottish Government wishes to procure research to validate whether the RDSAP 10 calculation method provides an appropriate estimation of wall u-values for Scottish homes. The overarching aim of this research is to: - to measure in-situ U-values for different existing stone wall material types to assess confidence in the current U-value equations published in RdSAP10 to predict Scottish stone wall U-values. - consider whether revisions to the stone wall U-value calculation algorithms are required in future home energy performance methodologies for existing homes. The outputs of this work should include: - U-value measurements for all assessed walls. - Assessment of walls following the RdSAP10 methodology. This should be undertaken by an experienced Domestic Energy Assessor. - Following a property survey, a desktop exercise in which lodgement of EPCs includes the calculation of U-values using the new equations (the before case), for each of the sample properties. - Commentary on the relationship between U-values obtained by measurement and calculated values. - Quantification of the impact on RdSAP calculations of any discrepancy between measured and calculated values. - If RdSAP calculated values differ by more than an appropriate error amount as agreed with SG, the Supplier should propose an alternative approach to U-value calculation. - Production of final report, including analysis and interpretation of sample results found, and written presentation of these to Scottish Government in the report.