Transparency
How We Calculate Recommendations
We believe in transparency. Here's exactly how we analyse your property and prioritise improvement recommendations.
Data Sources
EPC Advisor uses official government data to provide accurate, up-to-date information about properties in England and Wales.
DLUHC Bulk EPC Dataset
Our primary data source is the Open Energy Performance Certificates dataset published by the Department for Levelling Up, Housing and Communities (DLUHC). This dataset contains over 25 million EPC records for domestic properties.
- Updated monthly with new certificates
- Includes full property details and recommendations
- Published under the Open Government Licence
EPC Register API
For real-time lookups, we can also query the official EPC Register API to ensure you're seeing the most recent data available for your property.
Prioritisation Algorithm
Not all EPC recommendations are equal. We score each recommendation to help you focus on the improvements that offer the best value.
Scoring Formula
score = (w1 × EPC_points) + (w2 × annual_savings) - (w3 × cost_band) - (w4 × disruption)Each recommendation is scored based on four weighted factors, then ranked from highest to lowest score.
| Factor | Weight | Description |
|---|---|---|
| w1: EPC_points | 1.0 | Estimated SAP point improvement from EPC data |
| w2: annual_savings | 0.8 | Annual cost savings, normalised to 0-100 scale |
| w3: cost_band | 0.5 | Installation cost: Low=1, Medium=2, High=3, Very High=4 |
| w4: disruption | 0.3 | Disruption level: DIY=0, Minor trade=1, Major works=2 |
Display Rules
- Maximum shown: 5 priority actions (default 3, expandable)
- Minimum threshold: Score must exceed 10 to be displayed
- Tie-breaker: Lower cost first, then lower disruption
Partner Matching
When relevant, we show partner offers that match your property's specific situation. Partner modules are only displayed when:
- The improvement is recommended in your EPC data
- Your property type is eligible (e.g., houses for solar panels)
- The partner can service your area
We limit partner modules to a maximum of 3 per property report to keep the focus on your recommendations rather than advertising.
Affiliate Disclosure
Some partner links are affiliate links, meaning we may receive a commission if you proceed with a quote or purchase. This never affects our recommendations – we always prioritise based on EPC impact and cost-effectiveness, not commission rates.
Partner modules are clearly labelled with "Powered by [Partner]" badges.
Limitations
While we strive to provide accurate and useful recommendations, please note:
- EPC data accuracy: We rely on data from official EPC assessments. The accuracy depends on the original assessment quality.
- Cost estimates: Costs shown are indicative ranges based on typical installations. Actual quotes may vary based on your specific property.
- Savings estimates: Annual savings are projections based on typical usage patterns and energy prices at the time of assessment.
- Not professional advice: Our recommendations are informational only and should not replace professional assessments from qualified tradespeople.
For detailed information about our data sources and coverage, see our About Our Data page.
Related Pages
- What is an EPC? – Learn about EPC bands and what they mean
- 27 Ways to Improve Your EPC – Discover practical improvements for your property
- About Our Data – Data sources, coverage, and limitations