Will the Target Emission Rate change based on my heating choice?

In this series of articles, we aim to answer some of your questions about the upcoming changes to Approved Documents L and F, SAP methodology and the Future Homes Standard.

Current proposals suggest these regulations will be coming into force in England from October 2020. Contact us with your own questions about the regulation changes, or to discuss our training seminars and workshops.

Will the Target Emission Rate change based on my heating choice?

Homes using shared heating networks may have a relaxed target, but the type of fuel used will no longer have an impact.

The Target Emission Rate, and the new Target Primary Energy Rate, are calculated using the Model Design. This Model is based on the actual size and shape of your dwelling, but with preset U-Values and building services.

In England and Wales it doesn’t matter how you intend to heat your house, the Model Design is always based on a gas boiler heating system. This means your specification – whatever it may include – needs to perform better than a similar gas using a modern gas boiler.

When the Target Emission Rate was introduced into Building Regulations there were concerns this approach would unfairly impact rural developments which don’t have access to mains gas. It was therefore decided to adjust the Target Emission Rate when gas wasn’t used. For example, the current TER is increased by 17% if you are using an oil boiler, and by 55% if you use an electric heating system.

Under the proposed changes outlined in the Future Homes Standard, this relaxation is being scrapped to create a level playing field for all. There are two reasons for this:

Firstly, the Government is trying to discourage the use of carbon heavy fuels for heating our homes. Using oil heating systems without a relaxed TER will be very difficult indeed.

Secondly, electricity is no longer considered carbon heavy, so it’s not necessary to adjust the TER for electric heating systems.

That said, we need to remember AD L 2020 includes three targets, and although electric heating will perform well under the TER the use of panel heaters may struggle against the TPER and the Household Affordability target.

But it’s never that straightforward… a different type of target relaxation is being proposed.

This is because the new SAP methodology assumes much higher losses from District Heat Networks, which means dwellings fed by communal heating systems may show higher energy use and emission rates than those with individual heating systems.

As urban authorities (especially London) are keen to promote district heating networks, it is proposed the TER is relaxed for any dwelling using a shared heating and hot water system. This relaxation would be reviewed as the efficiency and losses from heat networks improves.

The public consultation which shapes the next version of AD L is open for feedback until February 7^th 2020.