Reductions in energy use
Comparison of bills before and after
Reductions in energy costs and/or alleviation of fuel poverty
Reductions in emissions associated with energy use
Improvement in internal comfort
Feedback from occupants of perceived improvement in internal conditions
Elimination of condensation, damp and mould
Reducing the risk of overheating
Improvement in energy rating (e.g. SAP)
Before and after RdSap calculations
Meeting a performance standard (e.g. NZEB or Passive House EnerPHit)
Improving the usefulness or sustainability of the building
Protecting the building against decay or deterioration
Improving resistance to water penetration and resilience against flood risk
Protection or enhancement of architectural heritage
Integration of energy efficiency measures with other improvements, e.g.
extension, loft conversion or general refurbishment
Any other issues that might be considered relevant