Understanding Plumbing Pipes: Choosing the Right Type for Your Project

Plumbing pipes are the unseen arteries of any building, carrying water in and waste out. Whether you're working on a new build, a renovation, or a simple bathroom upgrade, choosing the right type of plumbing pipe is critical. It affects not only the longevity and efficiency of your system but also its compliance with South African building regulations.

In this article, we'll explore the most commonly used plumbing pipes in South Africa, their applications, and how to decode the labels and markings on them.

🔧 Common Types of Plumbing Pipes in South Africa

1. uPVC (Unplasticised Polyvinyl Chloride)

• Uses: Cold water supply, waste pipes, and drainage systems.

• Features:

  • Affordable and lightweight

  • Resistant to corrosion and chemicals

  • Not suitable for hot water

• Markings to look for: Pipe class (e.g., Class 6 or Class 12), SANS 966-1 compliance, diameter (e.g., 110mm).

  
  

2. HDPE (High-Density Polyethylene)

• Uses: Cold water supply, irrigation systems, and underground piping.

• Features:

  • Flexible and impact-resistant

  • Good for areas prone to ground movement

  • UV-resistant variants available

• Markings: PN rating (pressure class), SDR ratio, SANS 4427 compliance.

  
  

3. Copper Pipes

• Uses: Hot and cold water supply, geyser installations.

• Features:

  • Long lifespan and heat-resistant

  • Naturally antimicrobial

  • More expensive and harder to install

• Markings: Pipe diameter, wall thickness, manufacturer stamp, SABS mark.

  
  

4. PEX (Cross-Linked Polyethylene)

• Uses: Hot and cold water supply, often in newer homes.

• Features:

  • Flexible and easy to install

  • Withstands high temperatures and pressures

  • Requires special fittings

• Markings: SDR rating, size (e.g., 16mm or 20mm), color-coded (usually red for hot, blue for cold), manufacturer details.

  
  

5. Galvanised Steel

• Uses: Found in older buildings.

• Features:

  • Prone to rust and corrosion over time

  • Being phased out in modern plumbing

• Markings: Pipe size, coating thickness, and manufacturer.

  
  

🔍 Decoding Pipe Markings and Labels

Just like cement or steel, plumbing pipes come with specific markings that tell you everything you need to know at a glance:

Label/Marking	What It Means
Diameter (mm)	Outer diameter of the pipe (e.g., 15mm, 110mm)
Pressure Rating (Class or PN)	How much pressure the pipe can handle (e.g., PN10, Class 6)
Material Code	uPVC, HDPE, PEX, etc.
SANS Standard	Compliance with South African standards (e.g., SANS 966-1, SANS 4427)
Batch Number/Date	Helps trace manufacturing origin and quality

Understanding these markings helps ensure you choose the correct pipe for the right purpose and stay compliant with regulations.

🛠️ Tips for Selecting the Right Plumbing Pipe

• Check the water temperature: Only use copper or PEX for hot water.

• Know your pressure requirements: Higher buildings or high-pressure systems need pipes with higher PN ratings.

• Use the correct pipe for buried applications: HDPE or class-rated uPVC pipes are ideal for underground use.

• Always verify compliance: Look for SANS-certified products to ensure quality and safety.

  
  

⚠️ Beware of Counterfeit or Low-Quality Pipes

Cheap, unmarked, or poorly labeled pipes may not meet safety standards and could lead to:

• Leaks or bursts

• Health risks (e.g., from chemical leaching)

• Failed municipal inspections

• Costly repairs

  
  

Always source your materials from reputable suppliers and check for official markings.

Final Thoughts

Plumbing may be out of sight, but it should never be out of mind—especially when it comes to choosing the right pipes. By understanding the differences between materials, reading the markings correctly, and selecting pipes based on your building’s specific needs, you can avoid costly mistakes and ensure a safe, long-lasting plumbing system.

If you're unsure, consult a qualified plumber or building professional who understands the local codes and conditions.