Criteria for Accessing Software for Approval for use in Building Regulations Energy Performance Calculations

Annex I to ODPM Circular 3/2006 sets out the methodology of calculation of the energy performance of buildings approved by the Secretary of State for the purposes of Regulation 17A of the Building Regulations 2000. The Annex signals that applications may be made to the Secretary of State for approval of commercial software calculation tools to form part of the methodology. The criteria for approval of software interfaces to SBEM, Dynamic Simulation Models and SAP 2005, and the procedures for applying are given below.

NCM Software Approval Service Procedure for Interfaces to SBEM

This document outlines the procedure for achieving approval for third party software interfaces to SBEM for use in checking building compliance with the Building Regulations (England and Wales) Part L2a only. It is likely that there will be an upgraded process for future use for software to produce building EPCs.

At the end of the process, either a recommendation will be made that the software should be approved in its current form, or a document listing the reasons why the software has not been approved will be produced. This document will be provided to the software vendor in order to assist them in achieving future compliance.

Third party interfaces should use the current version of SBEM at the time the approval process is completed.

The overall procedure is described below.

Information to be provided to BRE by software vendor

The software vendor will supply BRE with the following:

• 2 SBEM input files produced by the interface for the 2 sample building cases described in the attached building description documents
• software package name
• software version number
• vendor address, phone number and e-mail address
• the version of SBEM which the software uses

Preliminary Checking procedure

A number of checks of increasing stringency will be carried out. These are as follows:

1. check that the input file is compatible with the stated version of SBEM. SBEM should run correctly and produce a set of results using the input file
2. check of output values. Results should be in close agreement with those produced by running iSBEM for the 2 sample buildings
3. an analysis will be carried out in order to determine where the two input files differ

Once the checks are complete, a list of non-compliance issues will be produced (if any) and these will be supplied to the software vendor. The vendor should address any major issues (e.g. non compatibility with the stated version of SBEM or incorrect input) and resubmit their input files.

Once the input files are acceptable, a meeting will be arranged with the software vendor to carry out further checks and discuss any minor issues arising in the checking process as stated below.

Meeting with Software Vendor

For the meeting with the software vendor, the software vendor should arrange, together with BRE, for a computer to be available with the software installed and working so that the software can be run. The sample building cases should be available for viewing electronically in the software program. The purpose of this meeting is to:

• confirm that the input files were produced by the interface software. This will be achieved by the software vendor talking through some parts of the input process and producing the results files as submitted for the preliminary checking procedure above
• carry out further checks on the software. For example, this is likely to include checking that the default values are in line with those in iSBEM, checking that the U-values and CM values are calculated correctly, daylighting is considered acceptably and checking that NCM databases are being used correctly
• discuss any issues and, where possible, offer advice on how to resolve these in order to achieve approval

Recommendation

Following the meeting, if all the criteria tested by the checks listed above are satisfied, a recommendation will be made that the software should be approved. This will be provided in writing to CLG and copied to the software vendor in the 5 working days following the meeting. CLG will then issue the official acceptance to the vendor and to BRE. Once BRE have received the response from CLG, the software will be added to the list of approved interfaces to SBEM on the NCM website.

If BRE is not satisfied that the software should be approved in its current state, a document listing relevant issues will be provided to the software vendor in the 5 working days following the meeting in order to assist the vendor in achieving future compliance.

Detailed Simulation Models (DSMs)

Criteria

The criteria for assessment of applications for approval of DSMs are as follows. They must:-

a) be neither a monthly average nor a seasonal calculation method

b) satisfy all of the tests and other requirements defined within sections 2 and 3 of the document “CIBSE TM33:2006, CIBSE standard tests for the assessment of building services design software”

c) automatically generate the notional building exactly as specified in the SBEM User Manual, and do so as a distinct data file allowing the user to fully interrogate it

d) pass appropriate input and output data to SBEM as defined in the criteria for software interfaces starting at paragraph 2

e) be backwards compatible with all previous versions, i.e. they must be capable of reading previous versions’ data files or include a file conversion utility

Application submission process

Applicants must submit the following information both electronically and in hard copy

a) the name and version number of the software submitted for approval

b) the name, address and other relevant contact details of the applicant

c) results of all of the relevant tests, which must be within the stated tolerance bands defined in CIBSE TM33:2006, plus the electronic model files used for the calculations

d) confirmation that the notional building is automatically generated within the software

e) confirmation that the required summary input and output data is automatically exported to the approved compliance checking module

f) confirmation that the version of the software being nominated is not a monthly average calculation method

g) confirmation that any new version is backwards compatible with all previous versions

The hard copies of all material must be signed by an authorised representative of the software provider.

Assessment of the application

The application will be assessed in accordance with the criteria specified above. For quality purposes, the DCLG reserves the right to carry out “spot check” detailed assessments. Detailed assessments would involve a detailed examination of the electronic data files and possibly independent re-calculation of the test results. For detailed assessments, the software provider will be expected to provide the assessors with a version of the software in question and any technical support required free of charge for the duration of the assessment.

In all cases, software providers should be available to answer, free of charge, any queries from the assessors during the assessment.

Provided there are no delays in responding to assessors’ queries, it is expected that the assessment period will not exceed two weeks. The DCLG reserves the right to deny approval in unforeseen circumstances not included above which, in its opinion, make the DSM unsuitable for approval.

Application outcome

If a DSM is assessed as suitable for approval the name, version and software provider’s contact details will be added to the list of approved DSMs.

Where a DSM is assessed as not suitable for approval the applicant will be informed of the reasons behind the decision.

Note to users

Note that only the version (or versions) which are stated in the approved DSM list may be used for formal compliance checking: Beta versions, special versions and other variants must be approved before they can be used.

Further information

Further information can be obtained from Communities and Local Government (CLG) as indicated in Annex I to ODPM Circular 3/2006.

Criteria for assessing software implementations of SAP 2005

The criteria against which applications for approval of software implementations of SAP 2005 will be assessed are as follows:

a) it fully implements the SAP 2005 specification permitting all permutations of user inputs recognised by that specification: this includes the default data tables, input of separately calculated U-values, manufacturer's data such as boiler efficiency, BFRC window data, linear thermal transmittance for thermal bridging, pressure test result, measured cylinder loss, test data on solar collectors, provision to accept additional data that may be defined via Appendix Q, etc

b) it implements the Boiler Efficiency Database

c) it automatically generates the notional dwelling for the purposes of Part L assessments

d) it correctly calculates the SAP rating and the CO2 emissions for a series of test cases as adjudged by reference SAP 2005 software

e) it produces outputs covering:

• list of all input data to the calculation and summary of results (SAP rating, DER, TER, emissions in tonnes per year, primary energy in kWh per year)
• worksheet calculation of DER (as designed and as built), of TER and of SAP rating
• overheating assessment

Revisions are backwards compatible with all previous versions, i.e. they must be capable of reading previous versions’ data files or include a file conversion utility.