What is an SBEM?
Simplified Building Energy Model or as its known SBEM, is the preferred method for the government to assess energy in non-residential buildings. The calculations are extremely important, as they are used to show that the building complies with building regulations set in the Building Regulations Approved Document L2A. The SBEM works by comparing the designed Building Emission Rate (BER), with the Target Emission Rate (TER). SBEM calculations are somewhat similar to those SAP calculations with the difference being the SBEM ones are for non-residential buildings. They calculate the amount of energy used by a building by measuring the heating, air conditioning and lighting as well as the amount of carbon dioxide the building emits. It then assigns the building with a rating of 1 to 100. The closer to 100 it gets, the more energy efficient the building is deemed to be. A BRUKL certificate is then issued and if the project meets the requirements it will have passed the building regulations Part L. There are numerous types of buildings that need SBEMs, and these include (but are not limited to) the following
- Shopping Centres
- Offices
- Restaurants
- Retail Units
- Leisure Centres
- Retirement Homes
- Warehouses
In addition to those above it is important that an SBEM assessment can be not only for new builds, but also for refurbishments and extensions. There are some exceptions including buildings with no heating and places of worship.
Who needs an SBEM assessment?
An SBEM assessment is now a mandatory requirement for all new commercial properties with a size greater than 50m2. It can also be the case that an extension or a renovation project may need an SBEM calculation as well, but this changes in different circumstances.
When should be a SBEM assessment be carried out?
A SBEM assessment is split into two stages, design stage and as built stage. The first part (design stage) needs to be completed before the construction is started. It is vital to start the process in enough time, so that if any problems occur they can be resolved promptly and correctly. When this part is completed and the building complies with the regulations set in the document Part L, the construction can then go ahead and begin (as long as the local authority doesn't need any other assessments undergone, such as a BREEAM). When the building is built you can then do the second stage to the SBEM process, which is the as built stage and will include the results of an Air Test (if completed). After the SBEM is complete an Energy Performance Certificate can be issued.
What can be done to ensure a pass?
There are numerous factors to take into consideration when preparing to have an SBEM assessment completed. All off the following will give you the best possible chance of receiving a pass in the assessment. They Include,
- Ensure that the energy efficient lighting is fitted throughout the property.
- Making sure that the property is insulated to the best possible level it can be, making sure no heat can escape through the walls or ceilings.
- Ensure that the correct Air-Conditioning units are put in place dependant on the size of the property.
- Make sure the heating is relevant and suitable for the size of the building it will be heating
- Installing sufficient amount of ventilation that can be effective in all areas.
- Ensure that the property has a sufficient Air test result.
All these things will help you ensure your SBEM calculation comes back as a pass. As well as all these factors there are a lot more factors that can help you achieve a pass result.
What happens if the building doesn't pass?
Here at FEP we provide an accurate and fair representation, therefore, sometimes we do have to fail a building due to it not complying with the requirements stated in Part L of building regulations. If this is the case, then here at FEP, we will help you and advise you on the problems and how to get your project back on course.
When some companies complete a SBEM assessment, they only provide you with the result and fail to tell you the reasons it failed and how to rectify them. At Future Energy Performance though, we will provide you with all the reasons and solutions to the reasons it may have failed. In doing these possible changes we would then offer to do the retest for you in order for the SBEM to pass the assessment.
How is a new build SBEM calculation worked out?
Every building will have a (TER) Target Emission Rate, based on numerous factors. This will make up the benchmark that the building will have to comply with. If it doesn't, it will not pass the regulations on the document Part L.
To ascertain whether the building meets the standards required, we produce a Building Emission Rate (BER). In order to Pass the lower in order for the building to pass the assessment. TER is derived from the building model using building regulations, notional values, while DER uses actual values and compares the proposed plans against building regulation standards.
Reasons for failing a SBEM assessment?
Most common reasons for a fail in a SBEM assessment are quite possibly the easiest to rectify before the building is built. They are as follows
- Poor Lighting
- Not fully Air-tight as could be
- Incorrect services for the space required
These are just some of the factors that make an SBEM fail. If you can make sure all these are correct and appropriate for the space required, then providing the rest of the building regulations are met, it should rarely fail an SBEM assessment.