FAQS

SAP Calculations do three things:

1. They determine a SAP Rating (the energy related running costs of a dwelling)
2. They demonstrate compliance with Part L of the building regs
3. They are used to produce an Energy Performance Certificate (EPC)

SAP calculations are a requirement of the Building Regulations, and are required for all newly built dwellings in the UK. For more info see What are SAP Calculations?

TFEE stands for 'Target Fabric Energy Efficiency'. This is a target set for new build homes which looks specifically at the energy efficiency of the construction and the effects of air tightness and cold bridging. TFEE is measured in kWh/m2 per year. For more information see TFEE.

A SAP assessment involves modelling the shape and size of a new building along with its energy use. It’s this modelling of the building that provides the figures used on the EPC. Therefore, an EPC cannot be produced without completing a SAP assessment.

One of the Building Regulations requirements for extensions is that the overall increase in openings (windows, doors, rooflights) is limited to 25% of the increase in floor area. This is because windows etc. usually have more heat loss than a wall, for example. It is however possible to demonstrate that an excessive area of openings has been compensated for elsewhere in the design – and SAP Calculations are one way of achieving this.

If the assessor completing the as-built calculation did not also produce the design stage calculation, they will not have the SAP file available and therefore must measure the building themselves. Even if the assessor has the file available, they cannot reuse this for audit reasons. Because we always need to model a building, you will find that fees for SAP assessments are the same/similar whether this includes design stage assessments or not.

The final stage in the SAP Assessment process (for residential projects) is the issue of the Energy Performance Certificate. We've written a short blog on the subject HERE

SBEM is a method of assessing the energy performance of a non-domestic building. It is used to do two things:

1. To demonstrate compliance with Part L of the building regs
2. To produce an Energy Performance Certificate (EPC)

An SBEM calculation provides an output in the form of a 'BRUKL' report, which is required by building control prior to development commencing. For more information see What is SBEM and why use it?

DSM is a method of assessing energy performance in non-dwellings. It gives a more accurate result than other more simple methods like SAP or SBEM and is required for buildings of level 5 complexity. Level 5 buildings may have more complex attributes like atriums or automatic blind control. DSMs can also be used for lower complexity buildings if desired. For more information see our DSM page.

Over 40% of energy use in the EU is directly attributable to the operation of buildings, and 44% of UK carbon emissions come from buildings. Therefore addressing energy use and emissions in buildings is absolutely key in meeting our local and global commitments in lowering CO2 levels. In the UK our building regs and planning policy ensure that we design and deliver buildings that are not only good for our environment today but will continue to be for decades into the future too.

For typical building regs reporting, we aim to provide a 10-15 working day turnaround from the time of receiving all of your information and plans. Obviously this can vary if there are multiple dwellings to be assessed. If you need things done very urgently then just take up our Fast Track service, where we will guarantee to get things done in 48 hours.

We require your plans and a specification for the build outlining the building services and construction. Plans need to include a site plan, floor plans, elevations and sections.

We can work with almost any format as long as the drawings are to scale, or have a scale bar to measure from. We normally work with .dwg (CAD drawings) or .pdf files. We can also accept paper plans when necessary.

Yes. We are required by our accreditation bodies to retain your plans. Therefore if you need to retain hard copy plans, please make or send copies.

Following feedback from our clients and building control, we now send all reports and EPC’s in PDF format by email. If you do not have email access we can send a hardcopy version for a small fee.

Often clients have had design stage calculations carried out some time previously, but they may have lost contact with that assessor, or that assessor may not be qualified to issue EPC’s. For audit purposes it is unfortunately not possible for us to use someone else’s work and a new assessment will need to be carried out. We can then issue final reporting and EPC’s which are compliant and provide building control with everything they need.

U-values measure how effective a construction is at insulating. The U-value refers to the rate of heat transfer through a structure, and is measured in W/m2K. A lower U-value means a better thermal performance (less heat transfer). A U-value of a structure depends on the thermal resistance of each of the elements inside it, with most of the thermal resistance being provided by insulation.

As assessors we have to make sure that what you build onsite is an accurate reflection of the design. Therefore just providing a U-value at design stage is not enough information. We can either help you to create a full U-value calculation or take a calculation from another source. Full U-value calculations are also required as evidence at as-built stage.

Insulation manufactures like Kingspan and Celotex tend to provide U-value calculations involving their products free of charge, so it’s a good idea to contact their technical support folks first. Alternatively your SAP or SBEM assessor should be able to calculate them for you as part of their service.

Although it is possible to have diagnostic testing carried out at any stage, final testing should take place as late as possible, ideally when the build is complete. We always aim to provide a test date within 2 weeks of the request. We can often fit in urgent tests if required.

You need to ensure the building envelope is complete. All glazing, external doors and cladding should be complete. Light fixtures and sockets must be fitted, any penetration through the external walls and ceiling, i.e SVP and waste pipes, should be sealed. If you would prefer, BE can send you a full checklist to run through. For much more help see our Get your building airtight page.

All features which are designed for ventilation purposes should be closed or sealed, these include: extract vents, extract fans, window trickle vents, air conditioning ducts, and chimneys. All toilets, basins, and other wet drain areas must contain water to ensure a seal is made between the internal building space and sewerage system. Please do not tape or cover over anything else, as the engineer will have to remove it!

We are typically onsite for approximately one hour. We always try to leave time for a retest should it be required and small remedial works can be carried out.

Some of the measurements we take are very sensitive to noise and the presence of seemingly insignificant noises can adversely affect the test results. The best arrangement is for all trades to be suspended for the duration of the testing (approx 2 hours for a typical set of tests), or to send trades to another part of the site where their work will not affect the test area.

Rooms should be available in pairs, either vertically (separated by the party floor) or horizontally (separated by the party wall). They should be complete but unfurnished. This means:

• All wall and ceiling surfaces must be complete and skimmed
• Skirting boards, architraves and covings to be fitted
• All kitchen units in place
• Electrical sockets and switches to be in place
• Windows fitted and fully closeable with fully working trickle vents
• Internal doors in place and fully closeable.
• External doors to flats and houses to be fitted

Carpets and laminates should not be fitted as impact testing should take place on a bare floor, i.e. directly on the surface of the chipboard floating floor, or on the surface of the concrete floating screed.