Your guide to Boiler Plus 

On April 6 2018, changes to technical standards under Building Regulations Approved Document L1b (also known as Boiler Plus) came into effect and apply installations in existing buildings in England only.

The main changes are:

  1. Seasonal space heating efficiency of the new boiler no less than ErP 92%
  2. Time and temperature control required for all installations
  3. All combi installations must also include one of the following:
  • Weather compensation
  • Load compensation
  • Flue Gas Heat Recovery
  • Smart control with automation and optimisation

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In 2005 Approved Document L of the Building Regulations changed to require the installation of condensing boilers. Since then, there has been very little in the way of changes to minimum standards for heating installations.

In September 2015 the EcoDesign of Energy Related Products Directive (ErP) was introduced, which takes a more holistic view of heating system efficiency by recognising the impact of controls on the overall "package” of installed components.

The Department for Business, Energy and Industrial Strategy (BEIS) launched a consultation document in December 2016, and the subsequent policy changes concerning minimum requirements when installing boilers in existing buildings were effective from 6 April 2018, in England only.

The changes are not only beneficial to efficiency and emissions but are also easily adopted, low cost and simple to factor into a boiler installation:

  • Getting the best deal for consumers
  • Making it easy for installers
  • Attaining measured and sustainable fuel use reduction.

The table below provides examples of compatible controls that will help you comply with Boiler Plus.

View our guide to compatible controls and accessories here.

Frequently Asked Questions

  • What will happen if I don't comply?
  • What should I do if my customer doesn't want the extra measures?
  • Why are boilers rated differently for SEDBUK, SAP and ErP?
  • What support or training can you offer?
  • What is FGHR?
  • What is weather compensation?
  • What is load compensation?
  • Does uSense comply with Boiler Plus?
  • Where can I find more information?
  • When fitting a Plume Displacement Kit to a boiler, can I still install an IFOS?

It is a legal requirement to comply with Building Regulations, failure to do so could result in enforcement action. Further information on compliance and competent persons is available here.

There is also a duty on the householder to comply with Building Regulations please refer to the previous question for further guidance.

Because the method of calculation for boiler efficiency is different for all three ratings.

Our product training courses include an overview of the changes to the Building Regulations and what is required to comply. We will also provide information on our websites.

Flue Gas Heat Recovery (FGHR) is an energy efficient device that recycles the heat from the flue gases which would normally be expelled into the atmosphere and uses it to preheat domestic hot water.

Weather compensation is a device that communicates between the boiler and an outside temperature sensor. It tells the boiler to alter the flow temperature in relation to the weather outside, leading to fuel saving and a consistent environment.

Load compensation works by measuring the response of the heating system and controlling the flow temperature depending on the required load. When the boiler first fires, the increase in the return temperature is measured, giving an indication of the required load, and the boiler varies the flow temperature accordingly. The changes in the return temperature are then monitored and the flow temperature adjusted accordingly. This can reduce fuel consumption.

uSense complies with Boiler Plus when it is connected using Open Therm, because it provides load compensation functionality.

You can find the updated Domestic Building Services Compliance Guide here.

An IFOS can be fitted to a boiler when installed with a Plume Displacement Kit.

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