Part L1B – Refurbishments.
Summary of Methods to Demonstrate Compliance for Refurbishments
Reference method
- Demonstrate that any refurbished thermal elements meet minimum compliance standards (App C) if the renovated area in greater than 50 percent of the individual element or 25 percent of the external envelope. Elements of the same construction cannot be grouped. I.e., a house with 4 cavity walls has 4 individual cavity wall elements, not one. For internal work, only the external area of the rooms the work is carried out in is applicable for the requirement.
- Demonstrate that the work is not required to meet minimum standards as the simple payback period is greater than 15 years. This can be calculated by modelling the potential savings, in SAP software, of meeting the requirements, and comparing this with the cost incurred at installation.
- Demonstrate minimum standard compliance is not required as it would result in a 5 percent reduction in the room size, limit headroom, or cause problems with load bearing capacity or upstands.