What is the OD and wall-thickness tolerance of Hitze PEX-AL-PEX pipe?

Hitze multilayer pipe is manufactured to EN ISO 21003 dimensional limits in six size codes (1216/1418/1620/2025/2026/2632, i.e. OD 16/18/20/25/26/32 mm), each in 100 m coils, with a butt-welded aluminium core for full-length oxygen tightness. Measured OD and wall-thickness tolerances are documented in our Spec/TDS Pack, available on request.

Does PEX-AL-PEX pipe include an oxygen barrier?

Yes. The continuous aluminium layer makes the pipe fully oxygen-tight (0% oxygen diffusion), exceeding DIN 4726, so it protects boilers and steel manifolds from oxygen-driven corrosion in closed hydronic heating loops.

Is Hitze PEX-AL-PEX pipe suitable for both heating and potable water?

Yes. The five-layer structure serves radiant/hydronic heating and potable cold/hot water. Potable safety is supported to NSF/ANSI 61 and EU potable standards; certificate and listing numbers are available on request.

Product · Multilayer Pipe

PEX-AL-PEX Multilayer Pipe — Manufactured to German Standards

Five-layer composite pipe, engineered oxygen-tight for hydronic heating and certified-grade for potable water. One source for OD 16, 18, 20, 25, 26 and 32 mm, in 100 m coils — built to EN ISO 21003 and supplied to wholesalers, contractors and private-label brands across North America and Europe.

A true 5-layer PE-X / adhesive / aluminium / adhesive / PE-X build with a butt-welded aluminium core — the combination that gives multilayer pipe its shape retention, low thermal expansion, and a fully oxygen-tight barrier ordinary PEX cannot match.

Request Sample & Spec Sheet → Start Private Label →

Trade & bulk supply only — Hitze supplies wholesalers, contractors and importers, not end-consumers.

Multilayer PEX-AL-PEX pipe coils and export cartons stocked and container-ready in the warehouse

EN ISO 21003 · OD 16–32 mm

The Range

See the Multilayer PEX-AL-PEX Line

A true 5-layer composite — oxygen-tight aluminium core, potable-safe inner PEX, OD 16 to 32 mm in 100 m coils. Studio shots below show exactly what ships.

PEX-AL-PEX pipe coils and export cartons stocked and container-ready — Multilayer coils — stocked & container-ready

Boiler-room plant with white composite heating pipework, valves, pressure gauge and expansion vessel — In use — hydronic heating plant room

Cut-away of the 5 bonded layers — PE-X, adhesive, aluminium, adhesive, PE-X — labelled — 45° cut cross-section — the 5 bonded layers (PEX / adhesive / aluminium / adhesive / PEX)

Aluminium core being butt-welded on the pipe production line — Aluminium core — butt-welded seam close-up

Orange multilayer heating pipe running through the extrusion line — Orange multilayer heating pipe — on the line

Multilayer pipe in white, yellow, blue and orange lined up showing the bore — Colour range 16 → 32 mm — cut lengths lined up

White Orange

The Structure

What Makes a Five-Layer PEX-AL-PEX Pipe Different

A true multilayer composite pipe is not PEX with a foil wrap. It is five bonded layers, each doing a job.

Layer	Material	Function
1 — Outer wall	PEX	Abrasion resistance, handling durability
2 — Adhesive	Bonding layer	Locks aluminium to polymer (no delamination)
3 — Core	Aluminium (butt-welded)	100% oxygen barrier + shape retention
4 — Adhesive	Bonding layer	Bonds inner PEX to core
5 — Inner wall	PEX	Smooth, low-scale, potable-safe bore

Exploded 5-layer diagram with layers 1 to 5 numbered from outer PE-X to inner PE-X — Exploded 5-layer diagram — each layer labelled

Layer 1Outer PEXAbrasion & handling

Layer 2AdhesiveBond to core

Layer 3AluminiumOxygen barrier

Layer 4AdhesiveBond inner PEX

Layer 5Inner PEXPotable-safe bore

Oxygen-Tight

The continuous, welded aluminium core blocks oxygen diffusion (0%), beyond DIN 4726 — no oxygen ingress to corrode boilers or steel manifolds.

Shape Retention

Bend it by hand and it stays put — faster installs, fewer clips across both heating and potable runs.

Low Thermal Expansion

The aluminium core cuts linear expansion far below plain PEX, controlling sag and noise on hot loops.

See the Layer-by-Layer TDS →

Sizes & Coils

PEX-AL-PEX Pipe Sizes, Wall Thickness & Coil Lengths

One manufacturer, the full working range — six size codes from OD 16 mm to 32 mm, supplied in 100 m coils, white and orange.

Size Code	Outer Diameter	Structure	Coil Length	Colour
1216	16 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange
1418	18 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange
1620	20 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange
2025	25 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange
2026	26 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange
2632	32 mm	5-layer PE-X / adhesive / aluminium / adhesive / PE-X	100 m/coil	White & orange

Cut cross-sections of six pipe sizes labelled 16, 18, 20, 25, 26 and 32 mm showing the aluminium layer — Size wall 16 / 18 / 20 / 25 / 26 / 32 mm — cut cross-sections

Six size codes span OD 16 / 18 / 20 / 25 / 26 / 32 mm — one source for the full working range, each supplied in 100 m coils. Per-size wall thickness is detailed in the technical data sheet, available on request. See the 16mm & 20mm PEX-AL-PEX pipe sizes in detail →

OD / Wall-Thickness Tolerance

Parameter	Nominal	Tolerance
Outer diameter	OD 16 / 18 / 20 / 25 / 26 / 32 mm	Measured tolerance available on request
Wall thickness	Per size	Measured tolerance available on request
Aluminium core	Butt-welded, full-length	Continuous

Operating envelope: designed for continuous hydronic heating service and potable hot/cold water — pressure/temperature class per EN ISO 21003. Exact bar / ℃ ratings are detailed in the technical data sheet, available on request.

Download the Spec / TDS Pack

Full dimensional tables, tolerances, pressure/temperature ratings and material data sheets — every size, wall, coil and tolerance in one PDF. Business email required.

Request the Spec / TDS Pack →

Dual-Use Value

Why Specify PEX-AL-PEX for Heating and Potable Water

For merchants and contractors, PEX-AL-PEX is the pipe that lets one product line cover two jobs — cutting SKUs and simplifying installs.

Hydronic / radiant floor heating: the welded aluminium core is oxygen-tight, so no oxygen reaches the closed loop to corrode the boiler, pump or steel manifold — the failure mode plain PEX without an EVOH/aluminium barrier invites, and the reason DIN 4726 exists.
Potable cold & hot water: the inner PEX bore is smooth, low-scaling and supports potable safety standards (NSF/ANSI 61 in NA, EU potable standards) — suited to whole-house supply and risers — where an all-metal option is specified, compare our PPR-CU potable pipe. Certificate and listing numbers available on request.
Shape retention + low expansion make it a clean install in both applications: fewer fittings, less clipping, quieter hot runs.

Bottom line for buyers: stock one multilayer line, sell it into heating and plumbing, and cut the fittings and offcuts you’d carry across separate systems.

Split scene — radiant floor heating loops on the left and a potable water riser under a kitchen sink on the right — Split scene — radiant floor (left) meets potable riser (right): one pipe, both systems

Importers: one line, two markets — ask for the combined data pack covering heating and potable applications. Replacing a premium German brand? See how our 5-layer PEX-AL-PEX compares as a Rehau alternative →

Talk to Us About a Dual-Use Program → Underfloor Heating Pipe →

Standards & Proof

Built to EN ISO 21003 — and Documented for NA & EU Markets

Multilayer piping systems for hot and cold water are governed by EN ISO 21003. Hitze PEX-AL-PEX pipe is manufactured to that standard — with the dimensional, mechanical and long-term performance requirements importers and MEP consultants need to spec us in.

German-Tested, Catalog-Evidenced (Lead Credentials)

Credential	Body / Standard	What it proves
SKZ certificate	Süddeutsches Kunststoff-Zentrum (German plastics testing & certification institute)	Independent German testing of the material system
DIN 8077 / 8078	German pipe dimensioning & testing standards	Dimensional and quality conformity
EN ISO 15874	European polyolefin piping-system standard	System-level performance conformity

Composite piping-system pipes in blue, orange, white and grey with printed pipe markings along the wall — Pipe print detail — brand, size & standard markings along the wall

German brand credibility is further evidenced by German trademark registration No. 30 2020 005 484 (Deutsches Patent- und Markenamt, Munich).

Our management system is independently certified, covering the manufacture of PP-R, aluminium-plastic composite, PE-RT, PE, PEX and braided pipe together with joint fittings — evidence of a controlled, audited production process behind every coil.

ISO 45001 certificate of registration issued to the manufacturer, covering composite pipe and fittings manufacture — Independently certified management system — certificate on file

Standards & Documentation We Hold for NA & EU Markets

Market	Standards support
Europe / UK	EN ISO 21003 (multilayer), DIN 4726 (oxygen barrier), CE + DoP, DVGW, WRAS (UK potable)
North America	cUPC / UPC (IAPMO), NSF-14, NSF/ANSI 61 (potable), ASTM F1281/F1282 (PEX-AL-PEX)

SKZ Tested DIN 8077/78 EN ISO 15874 EN ISO 21003 DIN 4726 Oxygen Barrier cUPC / UPC (IAPMO) NSF-14 / NSF-61 DVGW WRAS CE + DoP

Hitze holds cUPC / UPC (IAPMO), NSF-14, NSF/ANSI 61, DVGW, WRAS and CE + DoP for NA & EU markets. The specific certificate and listing numbers are available on request / in the Cert Pack.

Download the Cert Pack

Market-by-market certificate and listing references for your submittal and audit file. Business email required · listing numbers available on request.

Request the Cert Pack →

System Compatibility

Matched Press Fittings — TH, U, F & M Profiles

A multilayer pipe is only as reliable as the joint. Hitze PEX-AL-PEX is dimensioned to press cleanly with our own press fittings — same source, verified fit, no guesswork on profile compatibility.

Press jaw crimping a fitting on multilayer pipe — TH / U profile

Press fitting on blue multilayer pipe showing brass body, stainless sleeve and plastic ring — Press fitting — body + stainless sleeve + plastic ring

Finished press joint on blue multilayer pipe with the sleeve crimped over the fitting — Finished press joint — pipe seated in the fitting

Across the OD 16–32 mm range and standard jaw profiles (TH / U / F / M), Hitze press fittings pair a brass body, stainless sleeve and plastic ring with the pipe they were engineered for.

Pipe + fittings from one manufacturer = one tolerance stack, one warranty conversation.
Confirm your press tool’s jaw profile against our range before you order.

Matched Press Fittings Pipe Technology & Material Science

View Compatible Press Fittings →

Buy or Build

Buy Wholesale or Build Your Own Brand

For Wholesalers & Distributors

One-source supply of the full OD 16–32 mm range (six size codes, 100 m coils), heating and potable. Consistent tolerance, documented compliance, and stock you can sell into two trades. There’s no MOQ — start with samples or a small trial order, then scale — and the matched Hitze pipe-and-fitting system is backed by a 50-year warranty. Ask for the current price list to plan your order.

Request a Quote →

For Private-Label Brands & Importers

German-standard manufacturing under your brand — your logo on the pipe, your artwork on the coil, EN ISO 21003 and NA/EU documentation behind it. No MOQ — start with samples or a small trial order — plus design confidentiality and a full ODM path from print to Cert Pack.

Start Private Label →

Branded pipe coils and palletised export cartons stacked on a warehouse rack — Private-label coils beside palletised export cartons

1974German brand, founded

118+Export countries

6Size codes, OD 16–32 mm

100 mPer coil

FAQ

PEX-AL-PEX Pipe — Buyer FAQ

What is the OD and wall-thickness tolerance?

For the ContractorHitze PEX-AL-PEX is made to EN ISO 21003 dimensional limits in six size codes (1216/1418/1620/2025/2026/2632, OD 16/18/20/25/26/32 mm), with a butt-welded (not lapped) aluminium core for full-length oxygen tightness and consistent press-fit results. Exact measured OD and wall tolerances per size are listed in our Spec/TDS Pack — request it to verify against your press tool.

Is the oxygen barrier really included?

For the ContractorYes. The continuous welded aluminium core is a 100% oxygen barrier (0% diffusion), exceeding DIN 4726. In closed hydronic loops that means no oxygen ingress to corrode the boiler, circulator or steel manifold — the exact failure plain non-barrier PEX invites in heating systems.

Is it EN ISO 21003 compliant?

For the Importer / MEP ConsultantYes — the line is manufactured to EN ISO 21003 for multilayer hot- and cold-water piping. Our material system is SKZ-tested (German institute) and built to DIN 8077/8078 and EN ISO 15874, and we hold DIN 4726, CE/DoP and DVGW in the EU and cUPC/NSF in North America — certificate and listing numbers are available on request / in the Cert Pack.

Can one pipe serve both heating and potable water?

For the WholesalerYes. The five-layer structure is rated for hydronic/radiant heating and potable hot & cold supply, so you stock one line for two trades. Potable safety is supported to NSF/ANSI 61 and EU potable standards. Available in six size codes, OD 16–32 mm, in 100 m coils.

What sizes and MOQ can you offer?

For the Private-Label BrandWe supply six size codes — OD 16, 18, 20, 25, 26 and 32 mm (codes 1216/1418/1620/2025/2026/2632) — in 100 m coils, white and orange, with your logo printed on the pipe. There’s no MOQ: start with samples or a small trial order and scale as your programme grows. Lead time and pricing depend on size mix and print, so request a quote for firm figures — and the matched Hitze pipe-and-fitting system is backed by a 50-year warranty.

In the Range

Matched Brass Compression Fittings

Beyond press systems, Hitze supplies nickel-plated brass compression fittings dimensioned for the same OD 16–32 mm multilayer pipe — one source for pipe and connectors, verified fit end to end.

Nickel-plated brass wall-plate seated female elbow with compression nut for multilayer pipe (product 64410) — Brass wall-mount seated female elbow with compression connection

Nickel-plated brass compression male elbow with threaded male end and compression nut for multilayer pipe (product 64406) — Brass compression male elbow with threaded end

Get Started

Request a Sample, Spec Sheet & the Cert Pack

Tell us your sizes (OD 16–32 mm), target market and volumes — we reply with pricing, MOQ and the EN ISO 21003 and NA/EU documentation for your region.

Request a Quote → Cert Pack →