How UPVC Pipe Diameter Determines Wall Thickness And Pressure Class

A uPVC pipe is not defined by outside diameter alone. The same OD can correspond to different wall thicknesses, pressure classes, and nominal weights depending on the specification logic. In the first section, the data is organized by OD and 4 Bar, 6 Bar, 10 Bar, and 16 Bar classes. The building drainage section follows a separate type-based structure.

This is why a 110 mm pipe is not always one fixed product. Diameter gives the size reference, but class or type helps define the actual structure.

One Diameter Can Have More Than One Structure

In the class-based section, one OD appears under several classes. As class increases, wall thickness increases. Nominal weight increases as well. This means the same diameter can represent different structural versions rather than one fixed pipe.

For specification work, OD is only the starting point. The full definition comes from the combination of diameter, class, wall thickness, and weight.

Typical Diameter, Class, and Wall Thickness Mapping

110 mm Pipe Reference

Pipe OD	Pressure Class	Wall Thickness	Nominal Weight
110 mm	4 Bar	2.2 mm	1.16 kg/m
110 mm	6 Bar	3.2 mm	1.64 kg/m
110 mm	10 Bar	5.3 mm	2.61 kg/m
110 mm	16 Bar	8.2 mm	3.90 kg/m

For 110 mm pipes, wall thickness rises from 2.2 mm to 8.2 mm as the class moves from 4 Bar to 16 Bar. Nominal weight rises from 1.16 kg/m to 3.90 kg/m over the same range.

160 mm Pipe Reference

Pipe OD	Pressure Class	Wall Thickness	Nominal Weight
160 mm	4 Bar	3.2 mm	2.41 kg/m
160 mm	6 Bar	4.7 mm	3.44 kg/m
160 mm	10 Bar	7.7 mm	5.47 kg/m
160 mm	16 Bar	11.9 mm	8.17 kg/m

The same pattern appears at 160 mm. Higher class corresponds to a thicker and heavier pipe within the same diameter group.

What Class-Based Data Means

For class-based specifications, the reading logic is direct:

• Diameter defines the size range.

• Class defines the pressure level.

• Wall thickness reflects the structural requirement.

• Nominal weight follows the same change.

A class-based chart is therefore more than a size list. It shows how one diameter can branch into different structural options.

Building Drainage Uses a Different Logic

The building drainage section does not use the same class-based structure. It is organized by type. The descriptive sentence mentions Type A and Type B, while the table itself lists Type B and Type BD, so this section should be read carefully as a separate type-based system.

Building Drainage Wall Thickness Reference

Pipe OD	Type B	Type BD
110 mm	3.2 mm	3.2 mm
125 mm	3.2 mm	3.2 mm
140 mm	3.2 mm	3.5 mm
160 mm	3.2 mm	4.0 mm
200 mm	–	4.9 mm
250 mm	–	6.2 mm
315 mm	–	7.7 mm

Here, wall thickness is organized by type rather than by pressure class. For larger drainage sizes, only the thicker Type BD values continue in the table.

Practical Use in Early Specification Work

A practical sequence is simple:

• Confirm the application.

• Confirm the OD range.

• Identify whether the requirement is class-based or type-based.

• Then read wall thickness and nominal weight as structural indicators.

This makes the specification easier to use in selection, comparison, and early technical discussion.