Question 1

Can I mix Speedfit fittings with Hep2O pipe?

Accepted Answer

Generally no — Speedfit (JG) fittings are designed for Speedfit pipe and copper. Hep2O pipe has a slightly different outside diameter tolerance and uses a different grab ring design. Mixing brands is not recommended by manufacturers and may void the warranty. However, both systems accept copper pipe, so copper can be used as an intermediary if needed.

Question 2

Do I need inserts in copper pipe with push-fit fittings?

Accepted Answer

No. Pipe inserts (stiffeners/liners) are only required in plastic pipe to maintain its round shape and prevent the grab ring from deforming the pipe. Copper pipe is rigid enough not to need inserts. Using an insert in copper pipe would restrict the bore and is not recommended.

Question 3

Can push-fit fittings be buried in walls or floors?

Accepted Answer

Push-fit fittings can be buried in screeded floors and plastered walls provided they are wrapped in a suitable lagging/protection to allow for thermal movement. However, best practice is to minimise buried joints. Some systems (like Speedfit) are WRAS-approved for concealed use. Always check the specific manufacturer guidance and ensure joints are accessible where possible.

Question 4

How do I remove a push-fit fitting?

Accepted Answer

Push the collet (release ring) towards the fitting body while pulling the pipe out. On Speedfit, use a Speedfit collet clip removal tool or flat-bladed screwdriver. On Hep2O, use the Hep2O demounting tool. The pipe can be reused if undamaged, but check for score marks from the grab ring. Fittings can typically be reused 4-5 times.

Feature	JG Speedfit	Hep2O	Polypipe PolyPlumb
Pipe material	PEX (cross-linked PE)	Polybutylene (PB)	Polybutylene (PB)
Sizes available	10, 15, 22, 28 mm	10, 15, 22, 28 mm	10, 15, 22, 28 mm
Accepts copper?	Yes (all sizes)	Yes (all sizes)	Yes (all sizes)
Insert required?	Yes (plastic pipe only)	Yes (plastic pipe only)	Yes (plastic pipe only)
Max. temp (continuous)	82°C	82°C	82°C
Max. temp (peak)	95°C	95°C	95°C
Working pressure	3 bar at 82°C	3 bar at 82°C	3 bar at 82°C
Pipe colour	White	Grey / white	Grey
Barrier pipe?	Yes (Speedfit barrier)	Yes (Hep2O barrier)	Yes (PolyPlumb barrier)

Fitting ↓ / Pipe →	Copper	Speedfit Pipe	Hep2O Pipe	PolyPlumb Pipe
Speedfit fittings	Yes	Yes	Not recommended	Not recommended
Hep2O fittings	Yes	Not recommended	Yes	Check manufacturer
PolyPlumb fittings	Yes	Not recommended	Check manufacturer	Yes

Pipe Size (mm)	Insert Required	Notes
10	Yes (plastic pipe)	Brand-specific insert
15	Yes (plastic pipe)	Most common size
22	Yes (plastic pipe)	Brand-specific insert
28	Yes (plastic pipe)	Brand-specific insert

UK Push-Fit Pipe Compatibility Guide

Push-Fit System Comparison

Cross-Compatibility

Pipe Insert Sizes

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