Future Homes Standard: Your Questions Answered

The Future Homes Standard is a 2025 UK building regulation requiring new homes in England to produce 75–80% less carbon than 2013 baseline homes. It mandates low-carbon heating (typically heat pumps), high insulation standards (wall U-values of 0.18 W/m²K), triple glazing (1.2 W/m²K), and mechanical ventilation with heat recovery (MVHR). The standard replaces SAP with the new Home Energy Model (HEM) for energy assessment.

The Future Homes and Buildings Standards regulations were laid in Parliament in March 2026 and come into force on 24 March 2027 for non-higher-risk building work. Higher-Risk Buildings follow on 24 September 2027. A 12-month transition period allows developers who submit plans by 24 March 2027 and commence construction by 24 March 2028 to complete to Part L 2021 standards. An updated SAP (SAP 10.3) is available for compliance from launch, with the Home Energy Model (HEM) following at least 3 months later.

No. The Future Homes Standard applies only to new-build homes in England. Existing homes are covered by separate regulations including Part L (conservation of fuel and power) for renovation works and MEES (Minimum Energy Efficiency Standards) for rented properties. However, FHS technologies and approaches — such as heat pumps and improved insulation — are increasingly being applied to retrofits.

Part L of the Building Regulations covers the conservation of fuel and power in buildings and has been updated multiple times. The Future Homes Standard is a specific, more stringent version of Part L that applies to new homes from 2025/2027. While Part L 2021 required a 31% carbon reduction over 2013 levels, FHS requires 75–80% reduction — a fundamental step change that effectively mandates heat pumps and very high fabric standards.

The FHS requires significantly improved thermal performance: external wall U-values of 0.18 W/m²K (compared to 0.26 under Part L 2021), roof U-values of 0.13 W/m²K, floor U-values of 0.13 W/m²K, and window U-values of 1.2 W/m²K (effectively mandating triple glazing). Airtightness must achieve 3 m³/h/m² at 50Pa, approximately three times tighter than the 2021 standard.

The FHS does not explicitly ban gas boilers, but the 75–80% carbon reduction target makes it virtually impossible to comply using a gas boiler as the primary heating system. In practice, this means heat pumps (air source, ground source, or hybrid) become the default heating solution for FHS-compliant homes. Some hybrid systems combining a heat pump with a gas boiler may technically comply in specific circumstances.

The Home Energy Model (HEM) is a new, more sophisticated whole-building energy model developed by government. It accounts for thermal mass, realistic occupancy patterns, actual heating system performance curves, and the interaction between building systems — factors SAP simplified or ignored. HEM is expected to become an approved calculation methodology no earlier than June 2026. However, the FHS launches with SAP 10.3 as the approved methodology, and both systems can be used during a dual running period of at least 24 months. HEM remains the government's preferred long-term methodology.

FHS U-value requirements are: walls 0.18 W/m²K, roof 0.13 W/m²K, floor 0.13 W/m²K, windows 1.2 W/m²K, and doors 1.0 W/m²K. These represent a significant improvement over Part L 2021 values and effectively mandate specific construction approaches — for example, the window U-value of 1.2 W/m²K requires triple glazing as standard.

The FHS does not prescribe specific heating systems but sets carbon reduction targets that effectively require low-carbon heat sources. Compliant options include air source heat pumps (ASHP), ground source heat pumps (GSHP), shared ground loop systems, heat networks (district heating), and potentially hydrogen-ready boilers in specific scenarios. The vast majority of FHS homes will use heat pumps as the primary heat source.

In almost all cases, yes. The 75–80% carbon reduction target under FHS cannot realistically be achieved with combustion heating. Air source heat pumps are the most common choice for individual homes, while ground source heat pumps or heat networks suit larger developments. The specific heat pump type and capacity should be determined by a heating design engineer based on the calculated heat loss of the dwelling.

Radiators for heat pump systems typically need to be 1.5–2× larger than those specified for gas boiler systems. This is because heat pumps operate most efficiently at flow temperatures of 35–45°C (compared to 65–80°C for gas boilers), and the lower temperature differential means each radiator emits less heat per square metre. A heating engineer should perform room-by-room heat loss calculations and size emitters using the correct delta-T for the design flow temperature.

The best emitter depends on the application. Underfloor heating offers the lowest flow temperatures (35–45°C) and maximises COP but has slow response times (1–6 hours) — heat pumps are typically run continuously to mitigate this. Skirting board heating offers a good balance — operating at 35–50°C with moderate response time while replacing conventional skirting boards, providing distributed heat around the room perimeter. Oversized radiators offer similar moderate response times at low flow temperatures, with the advantage of being familiar technology. Fan convectors deliver the highest output from compact units but produce some noise. Many FHS homes will use a combination of emitter types optimised room by room.

Yes — underfloor heating is one of the best emitter choices for heat pump systems. It operates at the lowest flow temperatures of any emitter type (35–45°C), which maximises the heat pump coefficient of performance (COP). The large surface area of the entire floor compensates for the low temperature. UFH is particularly effective in new-build FHS homes where it can be designed into the floor construction from the outset.

Skirting board heating is a low-profile heat emitter system that replaces conventional skirting boards around the perimeter of rooms. It uses hydronic (water-based) heat exchangers concealed within skirting-height casings, typically 150mm tall. The extended linear length provides substantial surface area for heat emission at low flow temperatures (35–50°C), making it well-suited to heat pump systems. Installation complexity is low as it follows existing skirting lines.

Industry estimates suggest FHS compliance will add approximately £5,000–£10,000 to the build cost of a typical new home compared to Part L 2021 standards. The main cost drivers are the heat pump system (£8,000–£15,000 installed, vs £2,000–£4,000 for a gas boiler), enhanced insulation, triple glazing, and MVHR installation. However, running costs should be lower due to the improved energy efficiency, and costs are expected to reduce as supply chains scale.

The FHBS comes into force on 24 March 2027. For non-HRB work, developers must submit relevant documents (initial notice, building notice, or full plans) to building control by 24 March 2027, and commence construction by 24 March 2028, to build to Part L 2021 standards. Higher-Risk Buildings have until 24 September 2027 to submit a valid Gateway 2 application. Historic 2013 transitional arrangements are being sunset — construction under 2010 standards must start by 24 March 2028.

Many aspects of FHS construction require new skills and knowledge. Heat pump installation requires MCS certification. MVHR commissioning requires specific training. Airtightness targets of 3 m³/h/m² demand higher construction quality and attention to detail at every stage. Industry bodies including the NHBC and FMB are offering training programmes. Early investment in workforce skills will be a competitive advantage.

FHS-compliant products are available from major building product manufacturers. Key categories include: heat pumps (Daikin, Mitsubishi, Vaillant, Samsung), MVHR units (Vent-Axia, Zehnder, Nuaire), triple-glazed windows (various manufacturers), insulation products meeting the required U-values, and low-temperature emitters including underfloor heating, oversized radiators, fan convectors, and skirting board heating systems. Always verify product performance data against FHS requirements.