How to install MLCP pipe
Updated: 23 October 2026
The coil is on the floor and the fitting is still in the bag. How to install MLCP pipe is the order of work, not a catalogue of the seven reels on the [MLCP pipe comparison](/hub/diy-supplies/mlcp-pipe). You cut the end square, prepare it the way that fitting's maker prints, bend without creasing the aluminium, and press once with the jaw that matches the profile. Then you test before anything is buried. None of these Amazon coils includes a cutter, a calibrator, or a jaw. A purchase through our links can earn a commission at no extra cost to you.
The coil is on the floor and the fitting is still in the bag. How to install MLCP pipe is the order of work, not a catalogue of the seven reels on the MLCP pipe comparison.
The coil is on the floor and the fitting is still in the bag. How to install MLCP pipe is the order of work, not a catalogue of the seven reels on the MLCP pipe comparison. You cut the end square, prepare it the way that fitting's maker prints, bend without creasing the aluminium, and press once with the jaw that matches the profile. Then you test before anything is buried. None of these Amazon coils includes a cutter, a calibrator, or a jaw. A purchase through our links can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Size stated | Coil length | Plastic named | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Adept Adept 16 × 2 mm PERT-AL-PERT, 50 m | 16 × 2 mm | 50 m | PERT-AL-PERT | 7.4 | about £64.99 | View offer |
| Alternative |  Adept Adept 16 × 2 mm PERT-AL-PERT, 25 m | 16 × 2 mm | 25 m | PERT-AL-PERT | 6.3 | about £36.99 | View offer |
| Best value |  Wärmer System Wärmer System 16 mm PERT-AL-PERT, 100 m | 16 mm × 2 mm | 100 m | Title says PERT-AL-PERT | 6.7 | about £74.99 | View offer |
On this page
Cut the end square and prepare it
Use a pipe cutter and take the end off square. A saw leaves a ragged lip and swarf in the bore, and the insert then starts out of round. Wavin's UK note says cut square, then calibrate and chamfer where that system asks for it, then press. On Tigris K1 and M1 the calibration and chamfer are part of the joint. On K5 and M5 the same maker only recommends them. A claim that you never need a reamer is not a rule you can carry from one bag of fittings to another.
The fitting in your hand is the instruction, not the brand on the pipe. If the sheet says calibrate, an unsized end can pinch the O-ring or sit short of the shoulder. Witness windows, where the fitting has them, show that the pipe is home before the tool cycles. A hacksaw cut on 16 × 2 mm can look finished after the jaw closes and still weep on test.
Bend it, and stop if the aluminium creases
Several UK manuals put the comfortable hand bend near five times the outside diameter. Maincor's product guide prints that as 80 mm on 16 × 2 mm pipe. Support the bend with a spring if the maker offers one. Do not use an open flame, and do not work the same spot twice until it whitens or flats. A tighter bend past a joist is how the aluminium creases. A sharp fold is not a curve you can trust.
Makers do not agree about a crease, so do not blend their repairs. Maincor says a buckled pipe is replaced or jointed out. Uponor says an MLC kink can be gently squeezed with soft pliers, and that a PEX kink can be warmed with a hot-air gun, never a naked flame, to a hand-warm maximum they print as 130°C. That hot-air step is the PEX sentence. It is not permission to warm a kink out of the Adept or Wärmer coil. If your sheet does not describe the soft-pliers repair, cut the crease out. Loop length is on the underfloor heating page.
Press once with the matching jaw
The jaw profile is part of the fitting. U, TH, and the other profiles are not interchangeable, and the jaw position changes with profile and diameter. A 16 mm TH jaw on a 16 mm U fitting can close the sleeve without making the joint the designer tested. Press once. A second squeeze can crack the sleeve or push the pipe back out. Where the fitting has witness holes, the pipe should be visible in them before the tool cycles.
Do not invent one UK pressure for every brand. Uponor points installers at its reading of BS EN 806-4. One screed guide says to keep at least 3 bar of water in the loops while the screed goes down. Another manual prints 6 bar for 24 hours before screed. An air test, where a maker allows one, stays at low pressure because air compresses. Follow the sheet you have. Close the floor only after that test has held. If the joint will be buried and you have no matching press tool, stop.
Where you stop
You stop when the pipe meets a heat source the class does not cover, when a joint will disappear under screed before it has been tested, and when the appliance is gas. Uponor's UK specification says not to connect its pipe directly to a heat source above the stated class. That is Uponor's reading for its pipe, so read your own sheet. Gas appliance work stays with a Gas Safe engineer. An unvented cylinder, a boiler connection you do not already understand, and a solid-fuel or solar primary are the same kind of stop.
Keep the loops full at the pressure your screed guide names, fixed so they cannot float, and free of joints in the bay if that guide forbids them. The first heat-up belongs to the floor system's instructions. If you are still choosing barrier PEX instead of MLCP, that decision is on the MLCP or PEX page, before the jaw comes out of the case.
Common questions
What order do I cut, prepare, and press?
Cut the pipe square with a pipe cutter, prepare the end exactly as the fitting sheet says, seat the pipe fully, and press once with the matching jaw. Check witness holes before you press if the fitting has them. Pressure-test before you close the floor or the wall. The coil brand does not replace that sheet. None of the seven Amazon reels includes the cutter or the jaw.
Do I always need a calibrator?
You need one when the fitting system says so. Wavin treats calibration and chamfer as required on Tigris K1 and M1 and only recommended on K5 and M5. Another brand's no-reamer line does not cancel the first system. If your insert's instructions name a calibrator, use it. If they say that generation does not need one, you still cut the end square.
How tight can I bend 16 mm pipe by hand?
Maincor prints a hand bend of five times the outside diameter, which is 80 mm on 16 × 2 mm. Use a bending spring if the system provides one. Do not use a flame, and do not bend the same spot twice. A tighter turn that flats the pipe is a crease, not a neat corner. Support the pipe so the bend forms as a curve rather than a fold against a joist edge.
Can I heat a kink the way people do with PEX?
Not as a general MLCP rule. Uponor allows a hot-air gun on a PEX kink, never a naked flame, up to a hand-warm maximum they print as 130°C. For multilayer, the same page talks about gently squeezing with soft pliers, and Maincor says a buckled section is replaced or jointed. Do not warm the Adept or Wärmer coil unless that pipe's own sheet says you may. If it does not, cut the kink out.
Do I pressure-test before the floor is closed?
Yes. The number is the one on your manifold and fitting instructions, not a single national figure. Uponor points at BS EN 806-4. One screed guide says at least 3 bar of water while the screed is placed. Another manual says 6 bar for 24 hours before screed. Air tests, where they are allowed, stay at low pressure because air compresses. Close the floor only after the test you were given has held.
When do I stop and call a plumber or a Gas Safe engineer?
Call a plumber when the joint will be buried and you have no matching press tool or no pressure test, and when the run meets a boiler or an unvented cylinder you are not competent to connect. Call a Gas Safe engineer for the gas appliance. Solid-fuel primaries and solar circuits are a stop as well. A successful press on a visible tail does not qualify you for those connections.
Related pages
Sources
Public UK sources listed below, plus the seven amazon.co.uk listings compared on this page. Listings captured 19 October 2026. Updated 23 October 2026.
- Water Supply (Water Fittings) Regulations 1999 (retrieved 23 October 2026)
- WRAS appropriate standards (retrieved 23 October 2026)
- Water Regs UK, BS 6920 note (April 2025) (retrieved 23 October 2026)
- Approved Document G (retrieved 23 October 2026)
- Approved Document L Volume 1 (2021, 2023 amendments) (retrieved 23 October 2026)
- BEAMA underfloor heating pipe guide (retrieved 23 October 2026)
- Uponor UK multilayer specification (retrieved 23 October 2026)
- ISO 21003-2:2008 (retrieved 23 October 2026)