Can a combi boiler be installed under the stairs in a 2-storey end of terrace house? The answer is yes, but there are specific regulations and requirements that must be carefully considered to ensure a safe and compliant installation. This comprehensive guide will delve into the technical details and provide a step-by-step approach to installing a combi boiler under the stairs.
Gas Regulations and Compliance
The installation of a combi boiler under the stairs must strictly adhere to gas regulations. These regulations are in place to ensure the safety of the occupants and the proper functioning of the boiler. A Gas Safe registered engineer must be consulted to ensure that the installation meets all the necessary requirements.
Key Gas Regulations to Consider
- The boiler must be installed in a well-ventilated area, with a minimum free air space of 5,000 mm² (7.75 square inches) for a boiler with a maximum heat input of 7 kW, and an additional 2,500 mm² (3.875 square inches) for each additional 3 kW of heat input.
- The boiler must be positioned at least 300 mm (11.8 inches) away from any combustible materials, such as wooden stairs or walls.
- The boiler must be installed in a location that allows for easy access for maintenance and servicing.
- The boiler must be connected to a suitable gas supply, with the correct pipe size and pressure.
- The boiler must be fitted with a suitable flue system that complies with the manufacturer’s instructions and the relevant building regulations.
Fire Boarding and Enclosing the Area
Depending on the specific installation, fire boarding or enclosing the area under the stairs may be required to meet safety standards. This is particularly important if the boiler is installed in a space that is adjacent to a living area or a bedroom.
Fire Boarding Requirements
- The fire boarding must be made of a non-combustible material, such as plasterboard or fire-resistant plywood.
- The fire boarding must be installed in a way that creates a continuous barrier between the boiler and the living space.
- The fire boarding must be sealed at all joints and around any penetrations, such as the boiler flue or pipework.
- The fire boarding must be installed in accordance with the manufacturer’s instructions and the relevant building regulations.
Flue Installation
The flue for the combi boiler must be installed correctly to ensure the safe and efficient operation of the boiler. The flue must be positioned in a way that meets the manufacturer’s instructions and the relevant building regulations.
Flue Installation Requirements
- The flue must have a minimum discharge height of 600 mm (23.6 inches) above the highest point of the roof.
- The flue must be positioned at least 300 mm (11.8 inches) away from any openable windows or ventilation openings.
- The flue can be installed horizontally through the external wall, but it must be positioned in a way that ensures the safe discharge of the combustion products.
- The flue must be made of a suitable material, such as stainless steel or aluminum, and must be installed in accordance with the manufacturer’s instructions.
Condensate Drainage
The condensate produced by the combi boiler must be properly drained to prevent any damage to the building or the surrounding environment.
Condensate Drainage Requirements
- The condensate drain must be routed directly outside through the wall, and it must not be connected to any foul waste or rainwater outlets.
- The condensate drain must be installed with a suitable gradient to ensure the efficient drainage of the condensate.
- The condensate drain must be made of a suitable material, such as plastic or copper, and must be installed in accordance with the manufacturer’s instructions.
- The condensate drain must be protected from freezing, either by insulation or by using a condensate pump.
Ventilation
Adequate ventilation is required to ensure the safe and efficient operation of the combi boiler. This can be achieved by venting to the outside or, in some cases, from inside the house.
Ventilation Requirements
- The boiler must be installed in a well-ventilated area, with a minimum free air space of 5,000 mm² (7.75 square inches) for a boiler with a maximum heat input of 7 kW, and an additional 2,500 mm² (3.875 square inches) for each additional 3 kW of heat input.
- The ventilation can be achieved by installing a permanent ventilation opening, such as a grille or a louvre, in the wall or the ceiling.
- The ventilation opening must be positioned in a way that ensures the efficient circulation of air around the boiler.
- The ventilation opening must be protected from the ingress of dust, debris, and insects.
Accessibility and Maintenance
Ensuring the accessibility of the combi boiler is crucial for maintenance and servicing. The boiler must be positioned in a way that allows for easy access and removal, if necessary.
Accessibility Requirements
- The boiler must be positioned in a way that allows for easy access to the controls and the front panel.
- The boiler must be positioned in a way that allows for the easy removal of the boiler, if necessary, for maintenance or servicing.
- The boiler must be positioned in a way that allows for the easy access to the gas and water connections, as well as the flue and the condensate drain.
Wall Type Considerations
If the walls surrounding the combi boiler are adjoining a neighbor’s property, additional considerations may apply.
Wall Type Considerations
- If the walls are shared with a neighbor’s property, the installation must comply with the relevant building regulations and party wall agreements.
- The boiler must be positioned in a way that ensures the safe and efficient operation of the boiler, without causing any disturbance or damage to the neighbor’s property.
- The boiler must be positioned in a way that allows for easy access to the boiler for maintenance and servicing, without requiring access to the neighbor’s property.
In conclusion, while it is possible to install a combi boiler under the stairs in a 2-storey end of terrace house, it is crucial to follow the specific regulations and requirements outlined in this guide. By consulting a Gas Safe registered engineer and ensuring compliance with all the necessary safety and building regulations, homeowners can safely and effectively install a combi boiler under the stairs.