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BER / TER CO2 calculations are required to demonstrate compliance with Part L2A for all new buildings other than dwellings.

As part of the "Competent Person" scheme, EcoConsulting undertakes certified TAS / SBEM calculations and assists in meeting Building Control’s most stringent energy and environmental demands. We also offer Energy Performance Certificates (EPCs) for all new-build buildings, both domestic and non-domestic. EPCs are now mandatory under UK law.



> Building Regulations - Part L  - Approved Documents 2006

  The new Part L (Conservation of Fuel and Power) 2006 revision of the Building Regulations entered into force on April 2006. Part L2 covers compliance requirements with all buildings other than dwellings, and is split into L2A for new buildings and L2B for existing buildings. In addition, all dwellings with a total floor area greater than 450m2 fall within Part L2.

Approved Document L2A has a new requirement to comply with the Target CO2 Emission Rate (see box to the right) which is demonstrated through approved software.

We were amongst the first to offer L2A compliance service under the “Competent Person” Scheme. We currently use TAS v.9.1, a commercial third-party software that is fully licensed by the Department for Communities and Local Government under Regulation 17A of the Building Regulations to demonstrate Part L2 Compliance.

TAS is a highly respected commercial software that has been developed by EDSL over 25 years ago to simulate energy consumption and thermal performance. A life-like 3-dimensional model is created in the software, which is then exported to the TAS Building Simulator. Results can be presented in a wide range of formats, although for our L2A Compliance Report we offer a standardized set of documents.

The final report will demonstrate compliance with Approved Document L2A: Conservation of fuel and power in new buildings other than dwellings:

- Criterion 1 – “Predicted CO2 emission from proposed building does not exceed the target” (BER/TER)
- Criterion 2 – “The performance of the building fabric and the building services systems should be no worse than the design limits” (Limiting values)

The results produced by TAS are highly accurate and have been verified—for example, TAS was used to simulate BRE’s exemplar Environment Building and the monitored results were almost identical to those simulated by iSBEM., the government's user interface developed to comply with Part L2A . However, iSBEM underestimates the benefits of energy-efficient measures; therefore the design team needs to “over-comply” with iSBEM: This results in massive compliance cost increases for the client –which are avoidable. We are thus able to save our clients money by using TAS, unlike some of our competitors using iSBEM.

TAS is also able to demonstrate compliance with Criterion 3 – “Limited the effects of solar gains in summer", which iSBEM is not able to do as it is too simple to undertake complex thermal energy simulations.

We also advise on designing an air tight envelope, to achieve compliance with air pressure leakage testing, which has become mandatory for all new constructions since April 6th, 2006.


> Complying with Building Regulations

> Energy Performance Certificates

Did you Know?


The new Part L 2006 measures will deliver increased energy standards for new buildings, estimated at around 28% in non-dwellings, 22% in houses, and 18% in flats.

On average, a 20% reduction in CO2 emissions per dwelling will be attained compared to a notional dwelling.







BER versus TER



Building Emissions Rate



Target Emissions Rate


BER is the predicted CO2 emissions of the building based on construction specifications.

TER is a target CO2 emissions rate established to achieve a 28% improvement to Part L 2002.

The new BER/TER Criterion 1 of Part L2 specifies that a new building's BER has to be lower or equal to the TER.

EcoConsulting   -   London, UK   -   Beirut, Lebanon l t I +961 (0) 1 971266   -   Information l e l