Part L (Conservation of fuel and power) and Part F (ventilation) have both been updated, alongside a brand new Part O for overheating in homes. These changes are expected to reduce emissions from new homes by around 30%. So if you’re in the process of planning or designing a new build, make sure you’re up to date with the latest regulations!
Greater insulation requirements
The changes to the minimum insulation standards and the way that the carbon emissions target is calculated will demand greater performance for new homes in SAP 10.
You’ll need to meet a set of reference U-values in order to pass SAP 10. These are based on what’s called a ‘notional’ dwelling. In theory, meeting all these notional values will result in a pass – but some can be quite hard to meet (like thermal bridging, opening areas and number of extract fans). That’s why the regulations allow for some design flexibility – you can do better or worse than the reference values, as long as you reach the TER.
Carbon factors mean greener power from heat pumps
Electricity from the national grid actually produces less carbon than mains gas, contrary to what SAP has assumed. This is because SAP is using an outdated carbon factor from 2012 – the measure of carbon associated with every kWh of energy use. In 2012, the national grid still had a reliance on coal-fired power stations, which have since been phased out. The real carbon factor for grid electricity has therefore been lower for some time.
Under the new regulations, a more accurate picture can be applied, which favors electric systems over gas and oil boilers.
The new carbon target is based on a notional dwelling that uses Waste Water Heat Recovery (WWHR). This means that if you don’t have this system fitted, the proposed design will need to make up for it in some other way. Please note that the notional dwelling also uses a gas boiler.
The new target primary energy rate is designed to help improve the efficiency of new homes. This rate, expressed as kWhPE/(m²·year), will help guide builders and homeowners towards more efficient dwellings that use less energy.
Improved performance for extensions
When assessing an extension to an existing dwelling, new requirements must be met. In the past, only a total CO2 emission rate was needed for compliance. However, both the dwelling and its proposed extension must now show compliance against a primary energy rate and whole dwelling fabric efficiency target. This will require more work from assessors and designers.
Air leakage testing for all homes
In the past, it was sometimes possible to test the air permeability of homes in certain cases, depending on the construction type and how well the SAP (Standard Assessment Procedure) performed. However, this has now been removed so that every unit will undergo consistent testing.
Part O for overheating
Overheating has always been a risk when it comes to building design and construction. In order to mitigate this risk, various assessment techniques have been developed by organizations such as the Greater London Authority and CIBSE. These techniques take into account factors such as the urban heat island effect and future climate change. These considerations are now reflected in Part O of the Building Regulations document.
Part S for EV (Electric Vehicle) charging
New homes and other buildings will now be expected to provide electric vehicle charge points and/or cable routes for future connection. This is governed under an entirely new Building Regulations document, Part S. This change will help to create a more sustainable future by encouraging the use of electric vehicles.
Now that we know about the new building regulations, it’s time to put them into action!
Make sure you comply with the new regulations to avoid any penalties or fees.
If you have any questions, our team of experts is always here to help.