Boiler regulations are there to protect more than just the gas supply.
If a funded standalone boiler installation is being installed and is not part of a funded government backed scheme , then this may not fall under the current PAS and will only need to follow gas safe and manufacturers instructions, unless a package that includes insulation has been developed as part of a funded scheme, this may change due to future legislation.
Installation Requirements and regulations.
Green, Information.
Amber Guidance.
Red Regulation.
Magnetic filter fitted. Some boiler manufacturers ask for this as part of warranty. The filter should be fitted to the return pipe on the heating. It is designed to trap rust and debris from the system before it goes through the heat exchanger.
Since 15 June 2022, fitting a magnetic filter is mandatory in the UK when replacing a boiler or installing a new central heating system. This requirement falls under Building Regulations Part L (Conservation of fuel and power) and complies with the BS 7593:2019 code of practice
Shock arrestor fitted, if boiler close to incoming water meter.
While there is no specific UK building regulation that mandates a shock arrestor simply because a boiler is close to a water meter, it is frequently required to meet Water Supply (Water Fittings) Regulations regarding pressure, and it is a strict requirement by most boiler manufacturers (MI – Manufacturer Instructions) to protect against damage.
To prevent water hammer, which can damage pipework and be annoying and loud.
Loft walkways should be introduced if boilers are being situated into a loft area and adequate lighting is a must.
The homeowner should provide measures as a minimum for their own safety and so that gas engineers can work in a safe environment. There should be a permanent means of safe access to the appliance. For example, this could be a permanently fixed retractable ladder to enter and exit the loft, with a safety guard around the loft access, which should be secured to the building’s fabric. The strength and design of the ladder should be such as to maintain safety. There should also be adequate fixed lighting.
A means to control each heat emitter (radiator thermostats, TRV’s). Regulation to allow each room to be individually controlled. Smart radiator thermostats are becoming popular. Some low temperature systems like heat pumps may not need thermostats on the radiators.
Section 5 (specifically paragraph 5.20) of the Approved Document L, Volume 1: Dwellings, 2021 edition (incorporating 2023 amendments.
The rear safety pipe safely positioned. If outside should be away from above doorways and walkways and pointed into the wall, if inside then should discharge to current regulations and should be visible.
The Gas Safety (Installation and Use) Regulations 1998 (GSIUR), specifically regarding safe installation and discharge. These must also comply with the Pressure Systems Safety Regulations 2000 (PSSR)
External condensate pipework to be insulated with a “class 0″ insulation and off ground. Condensate pipes can freeze in the winter. Protection using a class 0 insulation (usually black) prevents the insulation soaking up water and becoming a block of ice! Ideally the manufacturer will state size of condensate pipe to be used, if outside keep off ground and best practice is to terminate indoors. Some class 0 insulation comes with UV protection and some does not.
Condensate pipework is primarily regulated by BS 6798:2014 (Specification for installation and maintenance of gas-fired boilers), alongside UK Building Regulations and manufacturer instructions.
A means of programming (timer). Able to set on/off holidays and timed presets. Saves fuel as we have the system on and off as required.
The primary regulation for boiler programmers in the UK is Part L of the Building Regulations (Conservation of fuel and power), which was significantly updated in 2018 (Boiler Plus) and again in 2022 to improve energy efficiency
A means of interlocking to be present (a room thermostat can introduce interlocking on the boiler).
Boiler interlock, which ensures the boiler and pump turn off when there is no demand for heating or hot water, is required under Part L of the Building Regulations in England and Wales, specifically enforced through the Boiler Plus standards introduced in April 2018. It is mandatory for all new gas and oil boiler installations in existing homes to have this control functionality to improve energy efficiency.
Pipework to be insulated unheated spaces (lofts, garages etc). To prevent freezing and damage in the cold months.
Boiler pipework insulation in the UK is governed by Building Regulations Approved Document L (Conservation of Fuel and Power), specifically requiring compliance with BS 5422:2023. All primary circulation pipes for heating and hot water, including those in voids, must be insulated to reduce energy loss.
Installation to be carried out by a competent person. Gas Safe, Oftec, etc.
Gas boiler installation is governed primarily by the Gas Safety (Installation and Use) Regulations 1998 (GSIUR), which legally mandate that only a Gas Safe registered engineer can install, repair, or maintain gas appliances.
Boiler to be installed in a safe and accessible area. This is for maintenance and electrical safety, especially in areas that contain bathing facilities (bathrooms).
Flue to be accessible via removable boxing in or hatches. This is a regulation called flues in voids. The entire length of the flue should be able to be inspected.
Flues in voids must allow for inspection along their entire length to comply with the Gas Safety (Installation and Use) Regulations 1998 (GSIUR 26(9)) and Technical Bulletin 008.
A means of safely removing condensation from the boiler (soak away, drain etc). Condensate is acidic but not really dangerous (like lemon juice) but it can damage cement etc over time so it should be away from property walls.
Boiler condensate removal is primarily regulated by BS 6798:2014 (Specification for installation of gas-fired boilers) in the UK, which dictates that condensate must be discharged to an internal foul water system to prevent freezing. If external termination is required, pipes must be at least 30mm diameter and insulated.
Benchmark to be competed by installer. This is in the manufacturer’s supplied service book. It needs to be filled in so the installers address, contact number, name, and business can all be clearly read. It’s a tick box exercise to show the installer has signed off the installation.
While the “Benchmark Scheme” itself is an industry-led code of practice, it is recognized by the government as a means of demonstrating compliance with mandatory Building Regulations. Unfilled benchmarks can void warranty and class the installation as Uncommissioned and unsafe.
Flues should be at least 300 mm from openings into property (windows, doors etc). This is to stop products of combustion entering the property. A high level flue kit can be used in some circumstances to mitigate distance. Flues should be over 2m from ground. If not, then a flue guard is needed to protect from damage
Gas flue regulations in the UK (Building Regulations Approved Document J, BS 5440) require terminals to be at least 300mm–600mm away from doors/windows and 2m below roof levels to prevent exhaust reentry. Concealed flues in voids must have inspection hatches for safety checks
