EPC Survey costs to rise by June 15th

Kash Ijaz
6 days ago
3 min read

Understanding RdSAP 10: Why Survey Costs Are Set to Increase

The world of energy assessments is evolving. The upcoming release of RdSAP 10 (Reduced Data Standard Assessment Procedure) marks a significant upgrade in the methodology used for domestic Energy Performance Certificates (EPCs) in the UK. Scheduled for implementation on June 15, 2025, this update brings improvements in accuracy and better alignment with net-zero goals, but it also introduces more complexity—leading to increased costs for surveys.

So, what's behind the anticipated price hike? In short: more work for assessors.

What Is RdSAP 10?

RdSAP is the method used by energy assessors to calculate the energy performance of existing homes. Version 10, set to roll out on June 15, 2025, includes more data points, more detailed inputs, and new rules for how energy elements are recorded and assessed. (Energy Trust)

Why Will Survey Costs Rise?

The additional requirements in RdSAP 10 mean that assessors must spend more time on site, gather more detailed information, and often engage in extra post-survey analysis. This not only increases the time required per assessment but also the level of expertise and equipment needed—factors that naturally push survey fees upward.

Here's a breakdown of the additional work involved in RdSAP 10:

🧱 1. More Detailed Measurement and Recording

Floor areas by storey must now be recorded, not just total floor area.
Room height measurements are needed for each storey (not estimated or assumed).
Increased accuracy for window and door measurements, including their dimensions and positions.

🏠 2. Extra Construction and Fabric Details

Wall types must be broken down and recorded by percentage of area.
Floor and roof constructions must be categorised and evidenced more carefully.
Thermal bridging details must be specified using default values or known details.

🔧 3. More Heating System Data

Detailed inputs for heating controls, such as zoning, thermostats, and TRVs.
Specifics on secondary heating sources—their fuel type, control, and room location.
Heat pumps and renewable systems now require more nuanced entries.

🔌 4. Additional Data on Lighting and Appliances

Lighting now considers LED vs non-LED ratios and actual bulb types.
Presence of fixed mechanical ventilation systems must be identified and described.

🌡️ 5. Ventilation and Thermal Comfort Assessments

Assessors must consider the type and quality of ventilation systems.
New emphasis on identifying potential overheating risks, which may involve additional on-site observations.

📷 6. More Evidence and Documentation

Photo evidence requirements have increased, often with a need for specific angles or details.
Additional documentation or customer-provided data must be cross-referenced and validated.

What Does This Mean for Property Owners?

In practical terms, the changes in RdSAP 10 mean that:

Surveys will take longer—sometimes significantly so.
Assessors need to undergo new training and possibly invest in upgraded tools.
You're paying for greater accuracy and future-proofing—better data leads to better decisions for energy upgrades, grants, or compliance.

While the upfront cost may rise, the long-term value is higher-quality EPCs that support decarbonisation and smarter retrofit strategies.

Conclusion

RdSAP 10 is a step forward for domestic energy assessment. It ensures a more thorough, data-driven approach to evaluating a home's energy performance—but it also demands more time and effort from assessors. The result? A justified increase in the cost of surveys.

Still, this investment supports a cleaner, greener future—and gives homeowners and landlords clearer insight into improving their properties.