The 5-Step Statutory Action Checklist
Step 1: Audit Current Baseline Certificate. Visit the government's official Open Data portal. Check the construction age band and the specific recommendations list.
Step 2: Fabric-First Insulation Works. Hire TrustMark-accredited contractors to fill uninsulated cavities and top up loft insulation. Retain guarantee certificates (e.g. CIGA 25-year cavity guarantee) as assessors require documentary proof.
Step 3: Heating Controls Modernization. Install thermostatic valves on every radiator except the room containing the main wall thermostat. This simple step adds 2 to 3 vital points.
Step 4: Primary Heating Assessment. If your boiler is non-condensing (pre-2005), replace it. Check eligibility for the £7,500 Boiler Upgrade Scheme voucher for heat pumps.
Step 5: Official On-Site Re-Assessment. Instruct an accredited Domestic Energy Assessor (Elmhurst, ECMK, or City & Guilds). Provide your documentation folder so all hidden measures are factored into the software calculation.
| Retrofit Measure | Required Verification Document | Assessor Visual Inspection Rule |
|---|---|---|
| Cavity Wall Insulation | CIGA 25-Year Guarantee Certificate | Drill hole pattern on external mortar joints |
| Loft Insulation (300mm) | Invoice showing thickness / receipt | Direct physical ruler measurement in roof space |
| Double Glazing Units | FENSA or CERTASS Certificate | Date stamp inside pane spacer bar |
| Condensing Boiler | Building Regulations Compliance Cert | Make & model number plate on boiler chassis |
| Heat Pump / Solar PV | MCS (Microgeneration) Certificate | Inverter display & external compressor unit |
Common Pitfalls That Waste Money Without Gaining Points
Many landlords make the costly mistake of replacing single-glazed windows with standard double glazing, expecting a major jump in rating. Windows contribute only 1 to 2 SAP points but cost £4,000 to £8,000.
In contrast, cavity wall insulation costs under £1,500 and delivers 8 to 10 SAP points. Prioritize envelope insulation over cosmetic window replacements.