It’s now commonplace across the construction industry to make new-built houses as energy efficient as possible, with highly specified glazing, high levels of insulation and low air permeability rates all combining to reduce the emissions released by our homes. However, gas heating is still the preferred option for most house builders, be they individuals or large-scale developers. As we reduce our reliance on fossil fuels in other areas, heating for our homes is lagging behind.
The government announced this year its plan for net zero emissions by 2050, and highlighted our need to reduce the use of fossil fuels to heat our homes. It has now released a consultation on the new Future Homes Standard (FHS) that will be introduced in 2025. The new FHS will seek to enable a pathway for the 2050 net zero carbon target through the proposed reduction in energy demand and increased efficiency of the new housing stock. A key aspect of the FHS will be the banning of gas boilers in new homes. Other consultations and statements by the government have even indicated that the use of gas boilers in new homes could be banned even sooner.
Without the trusty gas boiler available to get new homes past their SAP calculations (in Part L of the Building Regulations), different technologies will be needed. This is where heat pumps come in. Powered by electricity, heat pumps turn electrical energy into heat very efficiently. Even better, as the grid becomes decarbonised through the use of large-scale renewables, the amount of carbon dioxide associated with 1kWh of grid-supplied electricity is reducing all the time – making highly efficient electric heating like heat pumps much more competitive against the incumbent default of the gas boiler. (This is due to be reflected in the upcoming Building Regulations update, SAP10). The high efficiency of heat pumps and lower carbon factor for grid electricity will likely make heat pumps the new SAP champion.
However, it’s worth bearing in mind: SAP calculations have a default efficiency of 170% for electric heat pumps, whereas in reality, some heat pumps are 350% efficient or more. To make sure you’re getting the most from your heat pump, especially when translating its real-world benefits into your SAP calculation, it’s important to make sure that the heat pump chosen for your build is listed on the Products Characteristics Database (PCDB). The PCDB is an online database of products where manufacturers upload the specifications of their products, so they can be used within the SAP software. This allows the maximum benefit to be obtained in your SAP calculation, and should give you that all important pass at Part L, with a high Energy Performance Certificate score.
If the chosen product is not present in the PCDB (and not all are!) then the default efficiency value must be used, which means the full potential of your efficient heating system isn’t being fully recognised within the SAP calculations. It’s important to note here that if the heat pump is installed by an MCS accredited installer, and an MCS certificate can be produced for the heat pump, this adds an uplift in the performance of the SAP calculations.
With the rolling out of new government legislation, updates to building regulations and the forthcoming new SAP10, as well as behavioural changes in society and an increased awareness of the need to move away from gas, heat pumps will be the cream that rises to the top of the next technologies.
To get the most out of your heat pump, it is important to consult your SAP assessor at Darren Evans Assessments Ltd. during the design stage, to make sure your chosen unit is present on the PCDB. Then its full potential can be used in the SAP calculation, winning that all-important green light for Part L, and making your journey to building a new home just that little bit easier.