Before you begin
What this tool needs
Describe the home as it is today, not the work you plan to do.
If the property already has a BER, use the official BER register instead of this estimate.
Reading the answer
What your result means
Treat the band as a range of roughly one band either way.
The suggested upgrade is the largest lever in this simplified model, not a cost-optimal retrofit plan.
Boundaries
Assumptions and limitations
Working assumptions
- Build era provides the baseline; heating, insulation, glazing and solar move it up or down in coarse steps.
- Official BER band thresholds are used, but the underlying score is not a DEAP calculation.
Where to be careful
- The model cannot see floor area, airtightness, thermal bridges, ventilation, orientation, exact products or hot-water details.
- Only a registered BER assessor can issue a rating or an advisory report.
Common questions
Questions about this tool
Is this a valid BER certificate?
No. It is an indicative estimate. A registered assessor must survey the home and use DEAP to issue a certificate.
Why can the result differ by a band?
Two homes of the same age can differ substantially in floor area, airtightness, thermal bridges, ventilation and installed products.