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Iplex K1® composite gas system is flexible enough to be bent by hand, is extremely light weight and corrosion resistant. In particular, no brazing or soldering is necessary. When installed by a trained and licensed tradesman, the system is of high quality and economical to use.

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Iplex K1® composite pipe and fitting gas system is designed for ease of installation of natural gas (NG) and liquefied petroleum gas (LPG) in residential and commercial buildings.

K1® Composite Gas Technical Guide


Iplex K1® composite pipes and fittings system offer the plumber an integrated system that has been well proven around the world. The systems advantages allow the plumber quick and simple installation, high performance, simple to handle on site and less risk of failures.

Features Benefits
Annealed copper crimp sleeve with a pipe inspection window Provides visible assurance the pipe has been pushed fully home to reduce risk of failure
No O-ring Prevents dislodgement or pinching during pipe insertions, delivery a more reliable seal
No 0-ring Larger internal bore for improved flow rates and less pressure loss
Lightweight and Flexible Easy to handle and install on site. Pipe can be bent by hand minimising the use of elbows and bends
Long pipe lengths Less joints and fittings
Corrosion resistant pipe Less risk of future failures or issues
Crimp connection No brazing or soldering
Fittings comes complete No addition of compression sleeves
Tamper proof jointing system Once the system is crimped it cannot be pulled apart
Interchangeable Tools Same tool can be used for K1® and Iplex's K2® and Pro-Fit® Systems


Product Details

Product Details

Standards and Approvals

Iplex K1® pipe is certified by DVGW (German Technical and Scientific Association for Gas and Water). Certification number DVGW DW-8217 AT 2505. K1® pipe and fiting are tested and conforms to AS 4176.

View Iplex Product Certifications


When installed by a licensed gasfitter and used correctly, as specified in AS 5061 and in accordion with iplex K1® gas installation instructions and training accreditation program; Iplex pipeline offers a 25 year warranty against material defects.


Iplex K1® Dometics Gas Warranty

K1® Pipe

Composite PE/AL/PE pipe

The multi layer composite pipe consists off 5 layers;

  • Inner layer:PE-HD, colour is yellow.
  • Coupling agent
  • Aluminium
  • CouplingAgent
  • Outer layer: PE-HD* colour is yellow.

Both the inner and outer layers comprise off high density polyethylene (PE-HD) which provides excellent impact strength.

The composite plastic aluminium pipe offers a lot of advantages besides the diffusion density: the pipe is dimensionally stable and still flexible. Fittings can be minimised due to the flexible nature of the pipe. The pipe is also corrosion resistant.

Dimensions of Iplex K1® composite pipe
Nom, outside diameter Mean bore
DN16 - 16 mm 12.0 mm
DN20 - 20 mm 15.5 mm
DN25 - 25 mm 20.0 mm
DN32 - 32 mm 25.9 mm
DM40 - 40 mm 32.0 mm
DN50 - 50 mm 41.0 mm


K1® Fittings

IPLEX K1® gas fittings are specially designed and engineered to complement the IPLEX K1® aluminium plastic composite pipe for gas use. The IPLEX K1® system has a comprehensive range of fittings that are suitable for general gas use. Each box contains an informative installation instruction leaflet

DR brass fittings

K1® brass fittings are fully dezincification resistant to Australian Standards and are precision CNC machined. OR brass is brass that has been heat treated and chemically enhanced to make it resistant to he loss of zinc i.e dezincificatior resistant. Brass that is not dezincificatior resistant can be subject to corrosion.

Copper crimp sleeves

All K1® fittings have a copper crimp sleeve with a pipe depth insertion window to provide visible assurance that the pipe has been pushed fully home.The copper crimp sleeves are held on the fitting by c distinctive "gas yellow" crimp sleeve retainer.

Dimensions of Iplex K1® composite pipe fittings
Nom, outside diameter Mean bore
DN16 - 16 mm 8.6 mm
DN20 - 20 mm 12.1 mm
DN20 - 20 mm 16.1 mm
DN32 - 32 mm 20.3 mm
DN40 - 40 mm 26.0 mm
DN50 - 50mm 34.7 mm
K1® Tooling

The range of K1® tools are engineered to ensure a simple, effective joint. The principle of this jointing method is extensively used around the world for gas, hot and cold plumbing and in-floor heating.

With crimping tools, care should be taken to ensure that moving parts are not damaged. Refer to individual tool instructions for maintenance and correct use. Calliper gauges are supplied with all tools to check that the copper ring has been properly crimped. Only use the correct Iplex tools to crimp the Iplex K1® composite pipes and fittings system.


K1® Domestic Gas - Sizing Tables
Installation & Testing

Installation & Testing

K1® Domestic Gas - Installation

Frequently Asked Questions

Frequently Asked Questions

Can Iplex K1® composite gas pipe and fittings be used in ground?

Yes, as fittings are DR (dezincification resistant) brass.

Can Iplex K1® composite gas pipe be used to connect directly to the gas meter?

Yes, providing any exposed pipe is lagged or sleeved as the pipe is not UV resistant. Iplex has a number of fittings available for such use.

Can Iplex K1® composite gas pipe be chased in masonry walls and floors?

Yes, the pipe can be chased into masonry walls with no protection necessary.

Can Iplex K1® composite gas pipe be embedded in concrete?

Yes, the pipe can be embedded in concrete but cannot contain any joints. Iplex recommends the pipe should be sleeved for best practice.

What warranty do I receive when I install Iplex K1® composite gas system?

When installed and used correctly for its intended purpose, as specified in the current edition of AS/NZS 5601, National Gas Installation Code and the Iplex Pipelines Installation Guide, Iplex Pipelines warrants K1® against manufacturing defects for a period of 25 years from the date of manufacture. Refer to the Iplex K1® Warranty Card for specific details (a copy can be downloaded from the Warranty section)

How close can Iplex K1® composite pipe be to high heat sources such as heating appliances and flues from heating appliances?

Iplex K1® composite gas pipe should be kept at least 500mm from such heat sources.

What distance should pipe be from slow combustion type stoves?

Iplex K1® composite gas pipe should be kept at least 1500mm from such heat sources.

What distance should Iplex K1® composite pipe be kept from recessed electric light fittings?

Iplex K1® composite gas pipe should be kept at least 300mm from such light fittings.

How close can Iplex K1® composite pipe be to gas or central heating vents or flues?

No closer than 150mm.

Can Iplex K1® composite pipe be used for the final connection?

No, however, with the use of transition fittings Iplex K1® composite pipe can be used to connect to copper or steel pipe.

What is the maximum working pressure of the Iplex K1® system?

70.00 kPa

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