🇬🇧
Plumbing \u00b7 UK

Plumbing & Heating Symbols — UK (BS 1553 / BS EN 806)

These symbols are used on plumbing installation drawings, heating system diagrams, and compliance certificates in the UK. They follow BS 1553-1 for graphical conventions and BS EN 806 for water supply systems. Plumbers, heating engineers, and G3 unvented specialists use these daily.

BS 1553-1:1977 / BS EN 806 / Building Regulations Part G14 symbols

Pipework

Hot Water Pipe

Hot water supply pipe

BS 1553-1

Cold Water Pipe

Cold water supply pipe

BS 1553-1

Waste / Soil Pipe

Waste water or soil drainage pipe

BS 1553-1 / BS EN 12056

Valves

Stopcock / Gate Valve

Manual water isolation valve (gate type)

BS 1553-1

Non-Return Valve

Check valve / non-return valve preventing backflow

BS 1553-1 / BS EN 806

Pressure Reducing Valve

Pressure reducing valve for mains water supply

BS EN 806

Components

Expansion Vessel

Pressurised expansion vessel for unvented systems

BS EN 806 / G3

Hot Water Cylinder

Hot water storage cylinder (vented or unvented)

BS 1553-1 / G3

Cold Water Storage Tank

Cold water storage cistern (header tank)

BS 1553-1

Radiator

Central heating radiator

BS 1553-1

Sanitary Appliances

Bath

Bathtub sanitary appliance

BS 1553-1

Wash Basin

Hand wash basin

BS 1553-1

WC (Toilet)

Water closet / toilet

BS 1553-1

Shower

Shower head / shower tray

BS 1553-1

Download this chart

Get a free branded PNG image of all 14 symbols. Print it, pin it to your workshop wall, or save it to your phone.

Frequently asked questions about plumbing symbols

What standard defines UK plumbing symbols?
BS 1553-1 covers graphical symbols for piping and plant. BS EN 806 covers design and installation of water supply systems. Together they define the symbols used on plumbing drawings in the UK.
Why are hot and cold pipes marked differently?
Hot water pipes are marked with red cross-bars and cold with blue. This helps engineers identify pipe runs on complex drawings without tracing them back to source.
What is a G3 qualification?
G3 refers to Building Regulations Approved Document G3, covering unvented hot water systems. Installing or working on unvented cylinders requires a specific qualification (typically from BPEC or similar).

Create plumbing certificates on your phone

CertBox has 166+ certificate types with built-in compliance checks, PDF generation, and instant sharing. Free to start.