In 2025, the UK housing sector will experience a significant shift as the Home Energy Model (HEM) replaces the Standard Assessment Procedure (SAP) for the energy rating of dwellings. This transition is part of the government’s broader initiative under the Future Homes Standard to enhance the energy efficiency of new homes and reduce carbon emissions.
Understanding the Home Energy Model
The Home Energy Model is a sophisticated framework developed to assess and rate the energy performance of new dwellings. It aims to provide a more accurate representation of a home’s energy efficiency, potentially influencing future housing designs, energy policies and building regulations.
Purpose of the Home Energy Model
The primary goal of the Home Energy Model is to ensure new homes are built to higher energy efficiency standards, contributing to the UK’s net-zero targets. It is specifically designed to align with the Future Homes Standard, which mandates that new homes from 2025 produce 75-80% less carbon emissions compared to current figures.
Comparison with SAP and EPC
As the UK prepares to transition from the Standard Assessment Procedure (SAP) and Energy Performance Certificates (EPC) to the Home Energy Model (HEM) in 2025, understanding the distinctions between these systems is crucial for all stakeholders.
Standard Assessment Procedure (SAP):
- Basis: SAP is currently the methodology used to assess and compare the energy and environmental performance of dwellings. It is based on the energy balance of a given property, calculating the energy cost associated with a standardised use of the home.
- Application: It is used for all new, converted, and some renovated dwellings in the UK.
- Output: The results of a SAP assessment are expressed through an Energy Efficiency Rating and an Environmental Impact Rating, which form part of the EPC.
Energy Performance Certificates (EPC):
- Purpose: EPCs provide a summary of energy performance related aspects of a building which includes energy efficiency ratings.
- Utility: These certificates are a requirement for properties being sold or rented in the UK. They inform potential buyers or tenants about the energy efficiency of the building, which can influence purchasing decisions and provide targets for energy efficiency improvements.
- Content: An EPC includes recommendations for cost-effective improvements to a building’s energy performance.
Home Energy Model (HEM):
- Innovation and Accuracy: HEM promises a more dynamic and realistic assessment by simulating actual energy usage patterns rather than relying on standardised theoretical scenarios used by SAP. It considers the effects of the building’s physical and thermal characteristics, occupant behaviour and local climate.
- Alignment with Modern Standards: Designed to align with the Future Homes Standard, HEM ensures that new homes are constructed to be significantly more energy-efficient and are compatible with low-carbon heating systems.
- Feedback and Development: The model is still under development, and its final form will be influenced by feedback from various stakeholders, including builders, environmentalists and governmental bodies.
Comparative Advantages:
- Real-World Scenarios: Unlike SAP, which uses idealised occupancy and heating patterns, HEM is expected to incorporate real-world data and adaptive behavioural patterns, offering a more accurate reflection of a home’s energy performance.
- Future Proofing: While EPCs provide a snapshot based on existing technology and standards, HEM is being designed to accommodate future technological advancements and changes in energy usage.
- Comprehensive Assessment: HEM aims to offer a more comprehensive understanding by evaluating a broader range of factors that affect a building’s energy performance. This includes the integration of renewables, the impact of thermal bridging and more precise ventilation modelling.
Impact on the Housing Sector
The introduction of the Home Energy Model is expected to revolutionise the way home energy performance is assessed, moving beyond the limitations of the existing SAP. It focuses on actual energy usage and factors influencing consumption, providing a more dynamic and realistic approach to energy assessment.
Future Prospects and Industry Participation
The development of the Home Energy Model is accompanied by extensive consultation and collaboration opportunities for professionals in the building and environmental sectors. Stakeholders are encouraged to participate in the developmental process by providing insights and feedback through government-hosted events and consultation platforms.
For those involved in building, designing or managing residential properties, now is the time to familiarise yourself with the Home Energy Model. Engaging with this new framework will not only ensure compliance by 2025 but also position your projects at the forefront of sustainable development. Consider attending upcoming workshops or engaging with consultation documents to understand how these changes may impact your business.
