JG Speedfit Push-Fit Fittings — 15mm and 22mm Couplers, Elbows, Tees, and Service Valves for UK Plumbers

JG Speedfit is the UK's most widely used push-fit plumbing system. Unlike compression or end-feed fittings, Speedfit requires no tools, no heat, and no flux — the internal collet grips the pipe and the O-ring seals it in seconds. This guide covers the key fittings in 15mm and 22mm, how they work, and which to use on different parts of a domestic install.

How JG Speedfit Works

Every Speedfit fitting contains two components that make no-tool connections possible:

• Collet ring — a stainless steel grab ring that bites into the pipe OD when you push it in, holding it against pull-out force
• EPDM O-ring — provides the water seal; rated to 10 bar at 95°C for standard fittings

To release the fitting, press the collet cap inward while pulling the pipe back. This is reversible, making Speedfit ideal for alterations and temporary connections.

Compatible pipe types: JG Speedfit works with copper pipe, JG Speedfit polybutylene barrier pipe, Hep2O flexible pipe, MDPE blue polythene pipe (with insert support), and most other BS EN ISO 15875 polybutylene pipes. Always use pipe inserts (tube supports) with plastic pipe to prevent collet bite-through and maintain bore size.

15mm vs 22mm — Which Do You Need?

Most domestic plumbing uses two pipe sizes:

• 15mm — feeds individual appliances: basin taps, bath taps, shower valves, radiator tails, WC cisterns, kitchen taps, washing machines, dishwashers. Also used for branch circuits from 22mm mains.
• 22mm — primary distribution runs: cold main from stopcock, hot flow/return from cylinder, central heating flow/return, bath supply where high flow rate is needed. Also used for direct-to-boiler connections.

Rule of thumb: if it's a single tap or valve, it's 15mm. If it's the pipe feeding multiple outlets or running from the boiler, it's likely 22mm.

Core JG Speedfit Fittings Explained

Straight Coupler (Equal)

The most basic Speedfit fitting — joins two lengths of pipe in a straight line. Used for extending runs, joining pipe after cutting out a section, or connecting pipe to an appliance flex hose using an adaptor. Available in 15mm and 22mm; reducing couplers are available for 22mm × 15mm transitions.

Common uses: extending a feed that's too short, rejoining pipe after isolating a section for repair, making up plastic pipe runs in loft or floor void.

Equal Elbow (90°)

Creates a 90-degree direction change without bending pipe. Invaluable in tight spaces — behind basins, in airing cupboards, around joists — where bending copper would be impractical or where plastic pipe needs to change direction without a bending spring. The push-fit design means it can be fitted in confined spaces where a compression elbow would need spanners.

Note: for low-profile elbow connections at walls (e.g. behind a basin or WC), use a wall-plate elbow with a back plate instead of a standard elbow.

Equal Tee (15mm and 22mm)

Creates a branch from a main run. In a 15mm circuit, a tee branches off a 22mm primary feed to serve a radiator pair, a basin, or a branch to a kitchen. In a 22mm circuit, a tee on the boiler flow feeds a separate zone or cylinder loop. Three-way connection with equal bore on all ports — for reducing branches, use a reducing tee (e.g. 22×15×15).

Unlike end-feed or compression tees, a Speedfit tee can be inserted mid-run without cutting the pipe completely — just cut the section, insert both ends, and the collets hold.

Service Valve (15mm)

An isolation valve with a Speedfit push-fit inlet and a 3/4" BSP male outlet — used to terminate a supply ready to connect to a washing machine, dishwasher, or undersink water filter. The quarter-turn handle gives rapid shut-off without disabling the rest of the system. 15mm Speedfit service valves comply with Water Regulations Schedule 2 Paragraph 15, which requires an isolation point on every supply to an appliance.

Common locations: below kitchen sink (cold mains for dishwasher or drinking water filter), under WC cistern close-coupled toilet inlet, undersink hot supply for washing machine, boiler condensate pump connection.

Speedfit vs Compression vs Press-Fit — Which to Use?

JG Speedfit's key advantage over compression is speed and access — no spanners, works in tight spaces, and can be refitted multiple times. Its advantage over solder is safety — no flame means no fire risk near timber, insulation, or gas pipework.

Installation Tips

• Deburr cut pipe ends. Always ream or file copper after cutting — burrs can damage the O-ring on insertion. Use a deburring tool or the reamer on a pipe slice.
• Use tube supports with plastic pipe. Polybutylene and barrier pipe are soft; the collet can bite through without a support insert. JG Speedfit superseal inserts are required in any push-fit fitting used with plastic pipe to maintain bore and prevent pull-out.
• Mark insertion depth. Mark the pipe with a pencil at the full insertion depth before fitting. A fitting not pushed home to the shoulder won't seal reliably.
• Test before boarding. After completing all push-fit connections, pressurise the system and check each fitting before enclosing in floor or ceiling voids. A failed connection is trivial to fix before boarding — much harder after.
• Support plastic pipe at intervals. BS EN 15875 polybutylene pipe needs support clips at 300mm centres (horizontal) or 500mm (vertical) to prevent thermal expansion sag. Use 15mm or 22mm pipe clips throughout.

JG Speedfit Fittings Available at APM Electricals

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