1 Make sure that your light bulbs are low energy bulbs
Under the new regulations, low energy bulbs are now acceptable in place of dedicated fittings. Making sure that you have a good proportion of low energy bulbs to standard bulbs has a big impact on the Dwelling Emission Rate (DER). This is an inexpensive but effective means of reducing CO2 emissions and aiding compliance.
2 Identify and reduce thermal bridging
We recommend that you calculate the Psi values for each thermal bridging junction. If you do not have accurate values then default values will be given – and the default values are quite conservative. Although calculating the accurate values will incur a cost, you will greatly reduce the Dwelling Emission Rate and thus avoid the need to change the design specifications of your build.
3 Lower the thermal mass
A low thermal mass (e.g. timber frame) means that the heating system does not have to heat the building fabric. This means that it will be easier to achieve a ‘Pass’ for your SAP – due to the lower dwelling heat demand and reduced carbon emissions.
4 Invest in your building fabric
It is possible to achieve compliance with Part L 2010 without the need for renewable technology if you can reduce your fabric U values. If the dwelling is to be assessed under the Code for Sustainable Homes, this approach will also gain you credits under Ene 2: Fabric Energy Efficiency.
5 Seal and insulate your party walls
With the heat loss from party walls now taken into account in the SAP calculation, it is important to ensure that you are not penalised for a U value of 0.2 in a party wall. It is possible to achieve a U value of 0 and no penalty by sealing the cavity, ensuring there is no air movement and fully filling with insulation.
6 Watch out for the air tightness confidence factor
Any dwelling that is not air tested at As Built stage will be subject to what is called a ‘confidence factor’. This is new, and means a figure of 2 is added to the average air test result on site and this figure is then used in the SAP. If your Site Managers are confident of achieving a low result, and your build schedule allows, it could be worth air testing every dwelling on smaller sites, to avoid incurring the penalty of the confidence factor.
7 Enhance your heating controls
Weather Compensators and where possible, twin zone control, will greatly reduce the DER, which means that it will be easier to achieve a ‘pass’.
8 Consider the SAP at an early stage in the design process
With solar gain having a large impact on the DER, designing a site layout to maximise this could save significant costs elsewhere on the build.
9 Consider renewable technology
For block compliance on flats it might be worth considering the use of renewable technology, where installation costs can be split over several dwellings and you could also take advantage of the Feed in Tariff (FIT).
10 Make sure your assessor is accredited
With ever evolving regulations, you need to make sure that the assessor you are using is up to date with the current regulations, and is aware of how they impact your build costs. A few pounds saved on a ‘cheap SAP’ could mean thousands of pounds spent due to poor advice.
Would you like to know more?
If you have any concerns about SAP assessments, please contact us today. An Energist SAP includes a GUARANTEED PASS, expert advice and a 48 hour fast track service. We are not just a company that inputs your details and leaves you with a problem if it doesn't 'pass'. We advise. We consult. We advise some more. And we always bring our considerable experience to help you to save money on your build. Let us take the hassle out of your SAP assessments today - ring us on 08458 386 387.