Reduced Data Standard Assessment Procedure
Energy Performance of Buildings Certificates: glossary, originally published by the Ministry of Housing, Communities & Local Government in 2014, defines the Reduced Data Standard Assessment Procedure (RdSAP) as: ‘…the government approved methodology for producing an EPC (Energy Performance Certificate) for existing dwellings. For existing dwellings much of the information required to assess the energy performance is not readily available so an on-site survey is needed to collect it. To minimise inconvenience for the homeowner, the method to assess energy performance was adapted to include a set of assumptions about the dwelling based on conventions and requirements at the time the dwelling was constructed. This means that less information is required from the homeowner for the assessment than for a newly constructed dwelling.’
On 15 June 2025, this software tool and calculation methodology which is used to create EPCs for existing buildings, the (rdSAP) will be updated from RdSAP v9.94 to RdSAP v10.0. It is the most significant change in the procedure in some 10 years, with a vastly increased number of data points that go towards the final rating and the inclusion of ventilation, as well as electricla heating systems such as heat pumps.
[edit] Related articles on Designing Buildings
- Approved document L.
- Display energy certificate.
- Emission rates.
- Energy certificates for buildings.
- Energy Efficiency Rating.
- Energy performance certificate EPC
- Energy Performance of Buildings Directive.
- Environmental impact rating.
- Minimum energy efficiency standard (MEES).
- National Calculation Method.
Featured articles and news
The benefits of engaging with insulation manufacturers
When considering ground floor constructions.
Lighting Industry endorses Blueprint for Electrification
The Lighting Industry Association fully supports the ECA Blueprint as a timely, urgent call to action.
BSRIA Sentinel Clerk of Works Training Case Study
Strengthening expertise to enhance service delivery with integrated cutting-edge industry knowledge.
Impact report from the Supply Chain Sustainability School
Free sustainability skills, training and support delivered to thousands of UK companies to help cut carbon.
The Building Safety Forum at the Installershow 2025
With speakers confirmed for 24 June as part of Building Safety Week.
The UK’s largest air pollution campaign.
Future Homes Standard, now includes solar, but what else?
Will the new standard, due to in the Autumn, go far enough in terms of performance ?
BSRIA Briefing: Cleaner Air, Better tomorrow
A look back at issues relating to inside and outside air quality, discussed during the BSRIA briefing in 2023.
Restoring Abbotsford's hothouse
Bringing the writer Walter Scott's garden to life.
Reflections on the spending review with CIAT.
Retired firefighter cycles world to raise Grenfell funds
Leaving on 14 June 2025 Stephen will raise money for youth and schools through the Grenfell Foundation.
Key points for construction at a glance with industry reactions.
Functionality, visibility and sustainability
The simpler approach to specification.
Architects, architecture, buildings, and inspiration in film
The close ties between makers and the movies, with our long list of suggested viewing.
SELECT three-point plan for action issued to MSPs
Call for Scottish regulation, green skills and recognition of electrotechnical industry as part of a manifesto for Scottish Parliamentary elections.
UCEM becomes the University of the Built Environment
Major milestone in its 106-year history, follows recent merger with London School of Architecture (LSE).
Professional practical experience for Architects in training
The long process to transform the nature of education and professional practical experience in the Architecture profession following recent reports.
A people-first approach to retrofit
Moving away from the destructive paradigm of fabric-first.
New guide for clients launched at Houses of Parliament
'There has never been a more important time for clients to step up and ...ask the right questions'
The impact of recycled slate tiles
Innovation across the decades.
EPC changes for existing buildings
Changes and their context as the new RdSAP methodology comes into use from 15 June.
Comments
[edit] To make a comment about this article, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.