Standards We Work To

Building Regulations and How They Relate to the Central Heating Products We Install

The rules for gas and oil installations are designed to protect you and your family and the standards are regularly improved. From 1 April 2005, all central heating boiler installations fall under the control of building regulations (the change applied to oil-fired central-heating boilers from 1 April 2007).

The new standards apply only if you decide to change your existing gas or oil fired central heating boiler or if you decide to change to a one of these boilers from another form of heating system.

How the Current Rules Apply to the Installation or Replacement of Gas Appliances

If you are planning to install or replace an existing gas or oil fired boiler, you need to choose a condensing boiler. This is a requirement of the Building Regulations Approved Document L1 for the higher standards for energy efficiency. The condensing boilers have to have either an ‘A’ or ‘B’ efficiency rating (A= greater than 90%, B= 86%-90%).

If there are exceptional circumstances, for example, where it is not practical or economic, a non-condensing boiler can be fitted and in this case an ‘exception certificate’ will be provided. Our installers will use the assessment procedure in Document L1 to decide if your circumstances are too difficult.

Completion Certificate

After a gas or oil appliance has been installed, you will receive a safety certificate (called a Completion Certificate) from either the Gas Safe Registered Installers Association (GAS SAFE) or Oil Firing Technical Association (OFTEC). You need to keep the certificate safe as it proves your appliance has been installed by a Gas Safe or OFTEC registered professional engineer and is also an essential part of the Home Information Pack (HIP), which became a legal requirement in England and Wales in 2007. For more information about the Home Information Pack, visit www.odpm.gov.uk.

Working Practices

Building Regulations also define how a central heating installer should work. The regulations refer to documents which give clear advice for any installer or homeowner. The two main documents are The Good Practice Guide 302 (GPG302) and Central Heating Standard Specification (CheSS – GIL059), which give two levels of control that will be deemed to satisfy the regulations “Good Practice” and“Best Practice”.

What is required?

Every time a boiler or hot water cylinder is changed, the whole heating system must be checked and brought up to the new standards of efficiency and control if necessary. This will ensure that the boiler will be able to work to its declared efficiency. After all, it would be a costly mistake to fit a new, highly efficient boiler if the rest of the system is inefficient.
The new boiler or cylinder must meet efficiency standards – SEDBUK for the boiler and BS for the cylinder. (NOTE: medium duty cylinders DO NOT satisfy these standards.)
The system should be fully pumped to be compatible with the higher efficiency boilers.
The system must have a boiler interlock, which is a means of shutting down the pump and boiler when no heat or hot water is required.
If a bypass circuit is fitted, an automatic bypass valve must be used.
Any controls fitted should be either Good or Best Practice as defined in CheSS or GPG302 documents.
When completed, the system must be commissioned to ensure that all components are installed and functioning correctly.

When installation of the central heating system is complete, the central heating engineer must explain the operation and maintenance of the system to the householder and instructions left with proof of commissioning (a completed and signed Benchmark Logbook is accepted).

Minimum Requirements to Fulfill "Good Practice" or "Best Practice" Requirements

For Good Practice, Stored Hot Water Systems should include:

Programmable controls (preferably with independent times for CH/DHW);
A room thermostat;
A cylinder thermostat;
Motorised valve(s);
Radiator thermostats throughout*;
An automatic bypass valve**.

For Best Practice, Stored Hot Water Systems should include:

A programmable room thermostat with capability to control a DHW room thermostat;
A cylinder thermostat;
Motorised valve(s);
Radiator thermostats throughout*;
An automatic bypass valve**.

For Good Practice, Combination Boilers should include:

A timer switch;
A room thermostat;
Radiator thermostats throughout*;
An automatic bypass valve**;

For Best Practice, Combination Boilers should include:

A programmable room thermostat;
Radiator thermostats throughout*;
An automatic bypass valve**.

* Radiator thermostats should be used on all radiators except where the room thermostat is fitted.

** If a bypass circuit is used, then an automatic bypass valve must be fitted.

Please note: for stored hot water systems, Sundial S, W and Y Plans satisfy Good Practice and Smartfit satisfies Best Practice.

References and Information

TACMA - A new guide - How to comply with the revised building regulations 2001/2002. This guide supports the official guidance covering the use of controls in domestic gas and oil fired boiler central heating installations within the revised Building Regulations, Part L1 for England & Wales and Part J for Scotland.
Guidance notes from the Energy Efficiency Partnership for Homes entitled "The Domestic Heating & Hot Water Guide to the Building Regulations 2001 - Part L1" is available from the DTLR.
A leaflet on the Building Regulations Part L1 is available from all merchants or download a copy from the Heating Controls Information website – TACMA.
Benchmark Logbook.
GAS SAFE is the Gas Safe Registered Installers Association
OFTEC is the Oil Firing Technical Association.
SEDBUK (Seasonal Efficiency of Domestic Boilers in the UK) is a British standard designed to be a realistic measure in practice.
Energy rating can be expressed in BTU (British Thermal Units) or kW (Kilowatts). To find the total energy produced or consumed they should be multiplied by time so that the units of energy become BTU (or kBTU) or kW/h. To convert from kW to kBTU/h, multiply by 3.413.