Underfloor heating

Stainless steel underfloor heating.

Corrugated 316L stainless steel for underfloor heating circuits. Easier to lay than PEX or MLCP, higher heat transfer once it’s down, lower mean water temperature for heat pumps.

Pro-FAST 15. Pro-FAST 17. Eco-MAX. Three sizes covering domestic refits through to commercial-scale circuits.

316L marine-grade stainless WRAS approved KIWA certified 100+ year design life UK designed

Why stainless underfloor

PEX is normal. Stainless is better.

Underfloor heating has run on plastic pipe for decades. Ridgeline Underfloor isn’t about replacing PEX for purity reasons. It’s about install speed, heat transfer, heat-pump efficiency, and a single-material story across the whole home.

  • Higher heat transfer

    Independent testing at the University of Manchester showed corrugated stainless underfloor heating up to 3.5× faster floor heat-up versus standard PEX systems. The corrugation creates turbulent flow, the metal conducts heat. Both work in your favour.

  • Lower MWT, better heat-pump efficiency

    Heat pumps love low mean water temperatures. Stainless underfloor delivers more heat per degree of flow temperature than plastic pipe, so the heat pump runs cooler and the COP holds up.

  • Lays down without a fight

    PEX and MLCP spring back, kink, and need a second pair of hands to keep them in place. Ridgeline corrugated stainless stays where you bend it. One-person job. Faster on the knees, faster off the slab.

  • Impossible to kink

    The corrugated geometry can be pulled, bent and threaded around an obstacle without losing the bore. PEX kinks under stress; this doesn't.

The range

Three sizes. One installation workflow.

From 15 mm domestic refits through to 22 mm commercial circuits, all in corrugated 316L stainless.

Ridgeline Pro-FAST 15 underfloor heating tube

Pro-FAST 15

The drop-in replacement for 15 mm PEX.

Compatible with everything. Standard overlay boards, castellated panels and the clip-down method (standard clips) all work. Pressure drop similar to 12 mm PEX, with a stainless water path and faster floor warm-up. Drops into existing PEX manifolds via the Pro-FAST adapter.

OD
15.0 mm
ID
10.0 mm
Coils
100 m · 200 m · 500 m
Ridgeline Pro-FAST 17 underfloor heating tube

Pro-FAST 17

Mid-size tube for larger domestic circuits.

Pro-FAST 17-specific overlay boards, or castellated panels and the clip-down method with standard clips. Pressure drop similar to 15 mm PEX. Useful where you need a slightly larger bore without committing to commercial-class circuits.

OD
17.2 mm
ID
12.2 mm
Coils
100 m · 200 m · 500 m
Ridgeline Eco-MAX underfloor heating tube

Eco-MAX

Longer circuits, commercial scale.

Larger-diameter underfloor tube for longer circuits and commercial projects. Requires Eco-MAX-specific overlay boards, or oversized clips for the clip-down method. Minimal pressure drop across long runs.

OD
22.4 mm
ID
16.6 mm
Coils
100 m · 200 m · 500 m

Full data sheets, pressure-drop tables, circuit-length guidance and design support: ridgelineunderfloor.com — the dedicated Ridgeline Underfloor design library.

Ridgeline Underfloor stainless steel tube being routed through an overlay-board system on site, with a fitting tool guiding the bend

Install speed

A one-person job. No fighting the tube.

Faster on the knees, faster off the slab. Standard overlay boards, standard PEX manifolds, no specialist tooling.

Heat pump synergy

A heat pump's favourite emitter.

Air source heat pumps run more efficiently when the heat-emitting circuits operate at lower mean water temperatures. Underfloor heating already helps because of the large emitter area — stainless underfloor pushes the advantage further by transferring heat into the floor faster.

In practice that means: lower flow temperatures from the heat pump, higher seasonal COP, and a heating system that does what a heat-pump install was designed to do. Pair Ridgeline Underfloor circuits with R-32 HP primary pipework for a full stainless steel heat-pump system, plant room to floor.

Ridgeline Underfloor stainless steel heating tube product close-up

Integration

Drops into the workflow you’re already running.

Ridgeline Underfloor doesn’t require a parallel toolkit or a proprietary manifold. Four practical points of integration:

  • Drops into PEX manifolds

    The Ridgeline Pro-FAST adapter slots into existing PEX connector cores on standard manifolds — no manifold replacement, no proprietary tooling.

  • Three install methods supported

    Overlay boards, castellated panels and the clip-down method all work. Compatibility varies by tube size. See each product card above for the specific match.

  • Screed and floating-floor installs

    The corrugated 316L tube is tolerant of the bend radii and clipping patterns used in both screeded slab and floating overlay systems.

  • Whole-home stainless ecosystem

    Pair Ridgeline Underfloor with Ridgeline tube on the primary circuit, P1 fittings at the manifold, Flexis at the heat-pump connections. One material, plant room to floor.

Suggested specification wording

Drop into your spec.

Underfloor heating circuits to use Ridgeline Underfloor corrugated 316L stainless steel tube — Pro-FAST 15, Pro-FAST 17 or Eco-MAX as appropriate for the heat-loss design and circuit length — on a Ridgeline-compatible manifold or via the Pro-FAST adapter on a standard PEX manifold.

Edit project-specific tube size, manifold and overlay-board references into this wording before issuing for construction.

Ready to install at full speed?

Get hands on with Ridgeline, or speak to the technical team about the right route for your next project.