Simplified Building Energy Model SBEM
The National Calculation Method (NCM) describes the procedure, for buildings other than dwellings, for demonstrating compliance with the carbon emission requirements of regulation 17C of the Building Regulations and calculating 'operational ratings' and 'asset ratings' in the production of Energy Performance Certificates (EPC's).
The NCM provides the underlying method and the standard data sets necessary to calculate the annual energy use of a proposed building and comparing it with the energy use of a 'notional' building of a similar type, under similar circumstances. This is done by calculating the Target Emission Rate (TER - the CO2 emission rate for the notional building) and comparing this with the Building Emission Rate (BER) for the proposed building. The BER must not be higher than the TER.
The calculations can be performed using approved simulation software (Approved Dynamic Simulation Models (DSMs)) or by using the Simplified Building Energy Model (SBEM), a computer programme developed by BRE and available to download from the NCM website. Unlike some of the DSM's, SBEM is a 'simplified' compliance tool, rather than a design tool.
The Simplified Building Energy Model was originally based on the Dutch 'Energy Performance of Non-Residential Buildings' (NEN 2916:1998). It has been available to demonstrate compliance with Part L of the Building Regulations since 2006, and for Energy Performance Certificates since 2008.
It calculates monthly energy use and carbon dioxide emissions, given a description of the building which is entered through its user interface iSBEM, based on:
- Building type.
- Building geometry.
- Construction.
- Use.
- Heating, ventilation and air-conditioning (HVAC).
- Lighting equipment.
A design stage SBEM assessment should be completed before the construction starts, and then an as-built SBEM when construction is completed, which includes the results of an air permeability tests and demonstrates the building has been constructed in accordance with the design. This is referred to as a Building Regulation UK Part L report (BRUKL).
2013 revisions to Part L of Building Regulations, which took effect on 6 April 2014 have been implemented in a new version of SBEM, cSBEM. SBEM may still be used on projects for which transitional arrangements apply, see 2013 changes to the approved documents for part L of the building regulations for more information.
[edit] Related articles on Designing Buildings
- 2013 changes to the approved documents for part L of the building regulations.
- Approved building energy calculation software.
- Air tightness.
- Approved documents.
- Building energy simulation software.
- Building Regulations.
- Dynamic Simulation Model.
- Emission rates.
- Energy Performance Certificates.
- Energy Performance of Buildings Directive.
- ISBEM
- National Calculation Method.
- Standard Assessment Procedure.
[edit] External references
- National Calculation Method.
- National Calculation Methodology (NCM) modelling guide (for buildings other than dwellings in England and Wales) 2010 Edition.
- cSBEM.
Featured articles and news
BSRIA Statutory Compliance Inspection Checklist
BG80/2025 now significantly updated to include requirements related to important changes in legislation.
Shortlist for the 2025 Roofscape Design Awards
Talent and innovation showcase announcement from the trussed rafter industry.
OpenUSD possibilities: Look before you leap
Being ready for the OpenUSD solutions set to transform architecture and design.
Global Asbestos Awareness Week 2025
Highlighting the continuing threat to trades persons.
Retrofit of Buildings, a CIOB Technical Publication
Now available in Arabic and Chinese aswell as English.
The context, schemes, standards, roles and relevance of the Building Safety Act.
Retrofit 25 – What's Stopping Us?
Exhibition Opens at The Building Centre.
Types of work to existing buildings
A simple circular economy wiki breakdown with further links.
A threat to the creativity that makes London special.
How can digital twins boost profitability within construction?
The smart construction dashboard, as-built data and site changes forming an accurate digital twin.
Unlocking surplus public defence land and more to speed up the delivery of housing.
The Planning and Infrastructure Bill
An outline of the bill with a mix of reactions on potential impacts from IHBC, CIEEM, CIC, ACE and EIC.
Farnborough College Unveils its Half-house for Sustainable Construction Training.
Spring Statement 2025 with reactions from industry
Confirming previously announced funding, and welfare changes amid adjusted growth forecast.
Scottish Government responds to Grenfell report
As fund for unsafe cladding assessments is launched.
CLC and BSR process map for HRB approvals
One of the initial outputs of their weekly BSR meetings.
Building Safety Levy technical consultation response
Details of the planned levy now due in 2026.
Great British Energy install solar on school and NHS sites
200 schools and 200 NHS sites to get solar systems, as first project of the newly formed government initiative.
600 million for 60,000 more skilled construction workers
Announced by Treasury ahead of the Spring Statement.