PPR is sized by outer diameter (OD) in millimetres, not by inches or nominal bore, which is exactly where sourcing mistakes start. This is the complete Bekaatherm PPR size guide: 20–63mm OD, real wall-thickness figures for every structure, the PN20/PN25 logic, and a clean mm-to-inch conversion for hot- and cold-water systems.
Bekaatherm supplies PPR pipe wholesale to importers, distributors & contractors, export-only, not single-item retail.
Three different sizing systems collide on a typical bill of materials, and mixing them is the #1 cause of ordering the wrong PPR diameter. Before you look at a single number in the size chart, it pays to be clear on which number you are reading:
The rule for PPR is simple and worth pinning to the wall of any sourcing desk: match by outer diameter in millimetres first, then translate to inch or DN for the paperwork, never the other way around. Get the OD right and the fittings, valves and welding sockets follow automatically. Get it wrong and an entire container of pipe can arrive one size out of step with the fittings that were ordered against an inch label.
Why does PPR use OD at all? Because polypropylene random copolymer pipe is pressure-rated by wall thickness against a fixed outer diameter. The extruder holds the OD constant and varies the wall to hit the PN class, so the OD is the one dimension that never moves for a given size, it is the natural anchor for the whole system. That is exactly how the standards are written: DIN 8077 tabulates PP pipe by outer diameter against an S-series wall, and ISO 15874-2 does the same internationally. That single design fact is the reason every Bekaatherm pipe, fitting and welding socket in this guide is catalogued by OD in millimetres.
Bekaatherm manufactures PPR pipe across the full standard range, 20mm to 63mm outer diameter, in plain PPR, PPR-AL-PPR aluminum-composite and fiberglass-composite structures, available in green, white and coffee series. Start with the quick OD-to-inch reference below; the exact wall-thickness figures for every structure follow in the next section. Inch values are nominal trade equivalents for cross-referencing an imperial BOM, not exact conversions.
| PPR Outer Diameter (OD, mm) | Nominal inch equivalent | DN cross-reference (approx.) | Typical use |
|---|---|---|---|
| 20 mm | ~1/2″ | DN15 | Fixture branches, small hot/cold runs |
| 25 mm | ~3/4″ | DN20 | Standard risers, apartment supply |
| 32 mm | ~1″ | DN25 | Main branches, manifolds |
| 40 mm | ~1-1/4″ | DN32 | Distribution mains |
| 50 mm | ~1-1/2″ | DN40 | Building risers |
| 63 mm | ~2″ | DN50 | Primary mains, commercial systems |
Inch and DN figures are nominal trade cross-references, not exact conversions, always verify against the mm OD before ordering. Diameters above 63mm are available on request.
This is the table most size guides never publish, actual outer-diameter × wall-thickness figures for all three Bekaatherm PPR structures, in both PN20 and PN25. Read it as OD × wall (for example, 25 × 3.5 means 25mm outer diameter with a 3.5mm wall). At the same OD, PN25 always carries a thicker wall than PN20; the aluminium-composite structure runs a slightly different wall because the aluminium layer shares the pressure duty.
Where these numbers come from. PPR dimensions are not a house style, they are standardised. The outer diameters and wall thicknesses below follow the German DIN 8077:2008-09 dimensional series for polypropylene pipe, with the general quality and testing requirements in DIN 8078:2008-09, and the internationally harmonised pipe requirements in ISO 15874-2:2013 (with amendments A1:2018 and A2:2022), part 2 of the ISO 15874-1:2013 series for PP hot- and cold-water piping systems (published in Europe as EN ISO 15874). Our PN20 wall is the S 3.2 (SDR 7.4) pipe series and PN25 the heavier S 2.5 (SDR 6) series in DIN 8077:2008-09 / ISO 15874-2 notation, which is why a 32mm pipe steps from a 4.4mm wall to a 5.4mm wall between the two classes. Note that DIN 8077 itself labels those two walls PN 16 and PN 20, so on a Turkish or EU tender always quote the S series or the wall, never the PN alone (see the tender section below). the heavier S2.5 series, which is why a 32mm pipe steps from a 4.4mm wall to a 5.4mm wall between the two classes. That means every figure in this chart is cross-checkable against a published standard, and a pipe from any compliant manufacturer should match it to within the standard’s tolerance band.
| OD (mm) | Plain PPR · PN20 | Plain PPR · PN25 | PPR-AL-PPR · PN20 | PPR-AL-PPR · PN25 | Fiberglass · PN20 | Fiberglass · PN25 |
|---|---|---|---|---|---|---|
| 20 | 20 × 2.8 | 20 × 3.4 | 20 × 3.1 | 20 × 3.4 | 20 × 2.8 | 20 × 3.4 |
| 25 | 25 × 3.5 | 25 × 4.2 | 25 × 3.3 | 25 × 4.2 | 25 × 3.5 | 25 × 4.2 |
| 32 | 32 × 4.4 | 32 × 5.4 | 32 × 4.1 | 32 × 5.4 | 32 × 4.4 | 32 × 5.4 |
| 40 | 40 × 5.5 | 40 × 6.7 | 40 × 5.0 | 40 × 6.7 | 40 × 5.5 | 40 × 6.7 |
| 50 | 50 × 6.9 | 50 × 8.4 | 50 × 5.5 | 50 × 8.4 | 50 × 6.9 | 50 × 8.4 |
| 63 | 63 × 8.6 | 63 × 10.5 | 63 × 7.0 | 63 × 10.5 | 63 × 8.6 | 63 × 10.5 |
A few things fall straight out of the numbers:
Figures are taken from the Bekaatherm product catalogue and reflect standard production to the DIN 8077 dimensional series and ISO 15874-2 pipe requirements. Tolerances, metre-per-bar weights and packing data are available on request.
A size chart carries more weight when every row maps to a catalogued product code you can actually order. Bekaatherm assigns a dedicated article-number band to each structure and PN class across the full 20–63mm range, so a sourcing agent can quote a specific SKU rather than a generic “25mm pipe”. The bands below cover the six standard sizes in each group.
| Structure & PN class | Article-number band | Sizes covered (OD) | Colour series |
|---|---|---|---|
| Plain PPR · PN20 | BK-001 → BK-006 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
| Plain PPR · PN25 | BK-007 → BK-012 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
| PPR-AL-PPR · PN20 | BK-01 → BK-06 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
| PPR-AL-PPR · PN25 | BK-07 → BK-12 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
| Fiberglass · PN20 | BK-13 → BK-18 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
| Fiberglass · PN25 | BK-19 → BK-24 | 20 · 25 · 32 · 40 · 50 · 63 | Green · White · Coffee |
Every diameter also has a matching fitting family molded to the same OD, sockets, tees, elbows, reducers and unions, so a 32mm pipe order pulls through 32mm sockets and welding sockets without a single adapter. The full fitting spectrum, from basic couplers to brass-insert threaded parts, is catalogued separately.
These aren’t stock photos of someone else’s pipe. This is Bekaatherm PPR pipe and fittings across the 20–63mm range, in green, white and coffee, with the brass-insert parts that pull through with them.
Two PPR pipes can share the same outer diameter and still be very different pipes. PN (Pressure Nominal) rates the working pressure, and for the same OD a higher PN means a thicker wall and a smaller bore. Bekaatherm PPR is produced in PN20 and PN25:
| Rating | Working pressure (cold) | Wall (same OD) | Bore (flow) | Best for |
|---|---|---|---|---|
| PN20 | 20 bar @ 20°C | Standard | Larger | General hot & cold water supply |
| PN25 | 25 bar @ 20°C | Thicker | Smaller | Higher pressure / temperature, heating risers |
The takeaway for sizing: the OD tells you what fittings and welding sockets match; the PN tells you the wall thickness and how much pressure and heat the pipe will take. You need both before you order. The rated pressure also falls as temperature rises, a pipe rated 20 bar cold carries far less continuously at 70°C, which is exactly why heating and hot-water circuits so often step up to PN25 or to a composite structure. Choose PN by the system’s working pressure and temperature, then confirm the exact wall thickness against the full table above or the technical data sheet.
Write the standard, the outside diameter with the wall thickness, and the pipe series — for example “PP-R pipe to TS EN ISO 15874-2 / DIN 8077:2008-09, dn 25 × en 4.2 mm, S 2.5 (SDR 6)”. A PN label on its own is not a specification, because the same wall carries different PN labels in different markets.
That last point is the one that costs importers money. In DIN 8077:2008-09, the German dimensional standard, the S 3.2 / SDR 7.4 wall (20 × 2.8) is labelled PN 16 and the S 2.5 / SDR 6 wall (20 × 3.4) is labelled PN 20. Across Türkiye, the Gulf and much of Asia the same two walls are sold as PN 20 and PN 25, which is the convention this chart and our catalogue use. A tender that says “PN 20 to DIN 8077” is therefore asking for 20 × 3.4, which in this catalogue is the PN25 line. Quote the S series or the wall and the ambiguity disappears: ISO 15874-2:2013 (with amendments A1:2018 and A2:2022) classifies pipe by S series and application class, never by PN.
| Pipe series S (ISO 15874-2) | SDR | DIN 8077:2008-09 label | Catalogue label (TR / Gulf / Asia) | Wall at 20 / 25 / 32 mm OD (mm) |
|---|---|---|---|---|
| S 5 | 11 | PN 10 | PN 10 | 1.9 / 2.3 / 2.9 |
| S 3.2 | 7.4 | PN 16 | PN 20 (this chart) | 2.8 / 3.5 / 4.4 |
| S 2.5 | 6 | PN 20 | PN 25 (this chart) | 3.4 / 4.2 / 5.4 |
| S 2 | 5 | PN 25 | rarely stocked | 4.1 / 5.1 / 6.5 |
| Source: pipe series and walls per ISO 15874-2:2013+A2:2022 and DIN 8077:2008-09; PN-to-SDR labels per DIN 8077:2008-09 as reproduced in the Wavin Pilsa PPR Product & Technical Manual. | ||||
Turkish public tenders and EU consultant specifications are checked field by field. The table below is the form we see accepted without queries; the right-hand column is the wording that triggers a clarification request.
| Field | Write this | Not this |
|---|---|---|
| Standard | TS EN ISO 15874-2 (EN ISO 15874-2:2013+A1:2018+A2:2022); dimensions DIN 8077:2008-09; quality DIN 8078:2008-09 | “ISO TYPE-5”, “DIN standard” |
| Size | dn 25 × en 4.2 | “3/4″ PPR”, “DN20” |
| Series | S 2.5 / SDR 6 | “PN 25” alone |
| Duty | Application class 1 (60 °C) or 2 (70 °C) with design pressure in bar, per ISO 15874-1:2013 | “PN 20 hot water” |
| Material | PP-R with the MRS class named (PP-R 80 or PP-RCT), virgin resin | “PPR” |
| Marking | Standard, dn × en, S series, class, batch and date printed along the pipe | unmarked or logo-only pipe |
| Evidence | SKZ certificate number and scope; ISO 15874-5 system test report; WRAS listing for potable lines | “CE certificate” (no CPR route exists for plastic pipe) |
| Source: ISO 15874-1:2013 and ISO 15874-2:2013+A2:2022 (classification), DIN 8077:2008-09 and DIN 8078:2008-09 (dimensions and quality); marking fields per ISO 15874-2 clause on marking. For what each ISO 15874 part certifies, see ISO 15874 part by part. | ||
Once the line item is fixed, the next question a project buyer asks is how many metres fit in a box. Pipe is volume-limited long before it is weight-limited in the 20–32 mm sizes, and the answer depends on whether bundles are telescoped (smaller pipe nested inside larger).
| Item | Figure | Planning note |
|---|---|---|
| 20GP | roughly 33 m³ usable against a ~28 tonne payload | Volume fills first on small-bore pipe; weight matters on 50–63 mm PN25 |
| Reference load | a 20GP takes roughly 8,000–9,000 m of 20mm PN20 pipe when bundles are telescoped | About 2,000–2,250 four-metre lengths |
| 40HQ | roughly 76 m³ | Used for OEM runs; MOQ one 40HQ, or 3 tonnes per colour on a first branded run |
| Mixed trial order | One 20GP mixed container (pipe + fittings + valves) | Typically about 60% pipe, 30% fittings, 10% valves by volume |
| Single-size MOQ | 500 kg per size and colour | Lead time 15–25 days on regular in-production sizes; 30–45 days OEM |
| Source: Bekaatherm export desk loading practice; volumes are indicative and depend on bundle configuration. Worked loading plans are in mixed-container planning for a 20GP. | ||
Two habits keep tender and container aligned. First, carry the S series onto the packing list and the certificate of conformity, so the pipe a customs officer or site engineer measures matches the document in his hand. Second, order fittings by the same dn: a socket for dn 25 fits both S 3.2 and S 2.5 pipe, because fittings are matched on outside diameter, not on wall. The dimensional logic behind that is worked through in DIN 8077 / 8078 read correctly.
Diameter follows flow. Undersize and you get pressure drop and noise; oversize and you waste material and container space. As a practical field guide:
Two variables beyond flow decide the final spec. Temperature: for heating and solar-thermal work, many specifiers step up to PN25 and to fiberglass- or aluminum-composite PPR for lower thermal expansion, a 4-metre plain-PPR run can move several millimetres between cold fill and hot service, while a composite run barely shifts. Distribution model: importers stocking a market usually carry a full 20/25/32 spread as fast-movers, then 40/50/63 to depth for projects, the size chart is also a stocking plan.
The 20–63mm range covers the whole spread of building services, potable cold and hot water, in-wall and in-slab heating, radiator connections and manifold distribution.
20–32mm branches carry hot and cold water to fixtures, heat-fused, buried and leak-free for the life of the wall.
40–63mm mains route through ceilings and risers, feeding whole floors from a single primary line.
PN25 and composite structures handle hot heating circuits, radiator tails and higher continuous temperatures.
32–40mm headers feed brass-core manifolds for underfloor and solar-thermal loops.
A size chart is only useful if the maker actually produces every line in it, in consistent tolerances, batch after batch. Bekaatherm does, backed by 30+ years of manufacturing, 1,000+ staff, 10,000 molds, a 120,000 m² plant and exports to 118+ countries.
| Manufacturing experience | 30+ years (PPR / PEX / PE systems) |
| Size range | 20–63mm OD, PN20 & PN25 |
| Wall thickness | 2.8mm (20mm) to 10.5mm (63mm PN25) |
| Structures | Plain PPR · PPR-AL-PPR · Fiberglass-composite |
| Color series | Green · White · Coffee |
| Workforce | 1,000+ staff |
| Molds | 10,000 sets |
| Facility | 120,000 m² |
| Export | 118+ countries |
| Certifications | SKZ · ISO 15874 · CE · WRAS |
| Dimensional standards | DIN 8077 / 8078 · ISO 15874-2 · EN ISO 15874 |
| Certificate numbers | Available on request |
| MOQ / lead time | One 20GP mixed container (pipe + fittings + valves) · 15–25 days on regular sizes |
Certificate numbers and copies are available on request.
For the Sourcing Agent: A 20mm PPR pipe is the smallest standard size and cross-references to roughly 1/2″ in trade terms. PPR is sized by outer diameter in mm, so match 20mm OD ≈ 1/2″, 25mm ≈ 3/4″, 32mm ≈ 1″, treat the inch label as a nominal reference, and confirm on OD before ordering.
For the Importer: We produce PPR from 20mm to 63mm outer diameter, in PN20 and PN25, across plain PPR, PPR-AL-PPR and fiberglass-composite structures, in green, white and coffee series. Larger diameters and full wall specs are available on request, enough range to stock every fast-moving size for your market.
For the Contractor: It depends on the class. A 25mm plain PPR PN20 pipe has a 3.5mm wall; the same OD in PN25 steps up to a 4.2mm wall with a smaller bore. Those walls are the DIN 8077 S3.2 and S2.5 series respectively, matching the pipe requirements of ISO 15874-2. Aluminium-composite and fiberglass structures follow the full table on this page, always spec OD, structure and PN together.
For the Contractor: By outside diameter (OD) in mm, unlike DN-based steel or PVC. A “32mm PPR pipe” is 32mm across the outside. When a drawing lists DN or an inch size, convert to OD first so pipe, fittings and heat-fusion sockets all match, this prevents the most common on-site mismatch.
For the Project Buyer: Our standard range tops out at 63mm OD (~2″), suited to primary mains and commercial risers, in both PN20 and PN25 (an 8.6mm and 10.5mm wall respectively). For diameters above 63mm or higher-pressure duties, contact our export team, extended sizes and technical data sheets are available on request.
This size chart is one spoke in the Bekaatherm PPR hub. Follow these to the parent product page, the pressure and structure guides, and the sourcing tools importers ask for most.
Tell us the diameters (20–63mm), pressure rating (PN20 / PN25), structure (plain / aluminum-composite / fiberglass), color and quantity, and our export team will price it. Prefer to compare first? Download the complete size chart with OD, wall thickness, PN and inch conversion.
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