RdSAP 10 changes include more detailed and precise data collection, leading to more accurate EPC ratings.
Key updates include:

• All windows are now individually measured and assessed.

• Insulation is recorded with more detail by location, type, and thickness.

• Heating systems and renewable technologies are modelled more accurately.

• Ventilation systems, including extractor fans and flues, are recorded in more depth.

• Air tightness is now part of the energy modelling, and measured values can be entered where a valid certificate exists.
  
  These RdSAP 10 changes lead to more tailored and realistic EPC results. Assessments may take slightly longer, but the final rating will better reflect the true performance of the property.