Underfloor heating (UFH) is increasingly popular in modern homes and renovations, offering sleek aesthetics and enhanced thermal comfort. However, property owners often wonder how installing UFH systems will affect their Energy Performance Certificate (EPC) rating. Will it improve energy efficiency? Does it hurt the EPC score due to higher electricity use?
In this article, we’ll unpack how EPC assessments evaluate underfloor heating systems, the pros and cons, and key tips to ensure UFH is properly accounted for in your EPC rating.
For professional EPC assessments that accurately reflect your underfloor heating system, visit our Services page.
1. Types of Underfloor Heating and Their EPC Impact
| UFH Type | Energy Source | EPC Efficiency Considerations |
|---|---|---|
| Wet (Hydronic) UFH Systems | Powered by gas boiler or heat pump | More efficient with condensing boilers or heat pumps; positively impacts EPC if well-insulated. |
| Electric UFH Systems | Electric heating mats or cables | Higher running costs; may reduce EPC scores unless powered by renewable electricity (e.g., solar PV). |
Wet systems are generally more EPC-friendly due to lower operating temperatures and better energy conversion efficiencies. Electric UFH systems, while convenient, can increase calculated energy consumption unless combined with renewables.
2. How EPC Assessors Evaluate Underfloor Heating Systems
During an EPC assessment, the heating system’s efficiency is factored into the property’s primary energy demand and CO2 emissions output. Key evaluation points include:
System Type (wet or electric).
Heat Source Efficiency (boiler, heat pump, etc.).
Zoning Controls and thermostats.
Insulation of floor slabs to reduce heat loss.
Underfloor heating works best in well-insulated properties where heat retention is maximised. If insulation is insufficient, EPC models may penalise the system’s overall efficiency.
For accurate EPC assessments of UFH installations, book an expert assessment with EPCrate.
3. Benefits of Underfloor Heating in Terms of Energy Efficiency
Even Heat Distribution: Reduces temperature gradients within a room.
Lower Flow Temperatures (Wet Systems): Operates at 35–45°C compared to radiators at 60–70°C.
Space-Saving Design: Allows for efficient use of living space without wall-mounted radiators.
Enhanced Efficiency with Heat Pumps: UFH is an ideal partner for air source and ground source heat pumps.
When paired with a high-efficiency heat source and proper insulation, UFH can significantly improve a property’s SAP score, leading to a better EPC rating.
4. Drawbacks of Underfloor Heating for EPC Scores
Electric UFH Systems Can Penalise EPC Scores: Unless powered by onsite renewables like solar PV.
Poor Insulation Cancels Out Benefits: Without insulated floor slabs, heat loss through the ground can increase energy demand.
Installation Quality Matters: Poorly installed UFH systems lead to uneven heating and inefficiency, which assessors account for in thermal modelling.
Lack of Smart Zoning Controls: Single-zone UFH systems can be less efficient than well-zoned radiator systems.
Learn more about how we assess and document UFH systems accurately on our About Us page.
5. Tips to Ensure Underfloor Heating Helps Your EPC Rating
Insulate Floor Slabs Properly: Ensure thermal breaks and high-quality floor insulation are installed.
Opt for Wet UFH Systems: Especially if combined with heat pumps or modern condensing boilers.
Integrate Smart Heating Controls: Zoning controls, thermostats, and programmable timers help reduce unnecessary energy use.
Provide Documentation to EPC Assessor:
System design and specification sheets.
Heat loss calculations.
Photos or certificates of floor insulation installation.
Combine with Renewable Energy (Solar PV): Particularly important for electric UFH systems.
6. EPC Case Study: UFH in a Renovated London Flat
A recent EPC assessment for a London flat retrofit showed:
Original EPC Rating: E
Upgraded with:
Wet UFH system connected to a high-efficiency gas boiler.
Floor insulation with 100mm rigid boards.
Zoning controls for living and sleeping areas.
New EPC Rating: C
The property’s improved thermal efficiency and lower energy demand resulted in a two-band uplift on the EPC report.
For EPC assessments that reflect your UFH improvements accurately, visit our Pricing page for competitive rates.
Conclusion
Underfloor heating can be a beneficial addition to your property’s energy profile, but its impact on EPC ratings depends on system type, insulation quality, and supporting technologies. Wet UFH systems, when correctly installed and paired with efficient heat sources, generally enhance EPC outcomes. Electric UFH systems require careful integration with renewables and smart controls to avoid EPC penalties.
At EPCrate, our assessors are trained to document every efficiency measure—ensuring your underfloor heating installation is accurately reflected in your EPC rating. Schedule an EPC assessment via our Booking page or reach out through our Contact page for tailored advice.
