How to Install PPR Pipes: Welding, Fittings and Testing (2026 Guide)

PPR (polypropylene random) pipes are joined by heat welding: pipe and fitting melt together into one piece. Done right, the joints never leak.

Tools You Need

• PPR welding machine with dies for each size.
• PPR pipe cutter (20–32 mm or 40–63 mm).
• Tape measure and marker.
• Clean cloth; spirit level; pipe clips.

Step-by-Step Welding

1. Switch on the welder and wait until it reaches temperature (light changes).
2. Cut the pipe square and clean off burrs.
3. Mark the socket depth on the pipe.
4. Push the pipe into the female die and the fitting onto the male die at the same time.
5. Heat for the time in the table below.
6. Remove both and push straight together to the mark; do not twist.
7. Hold still for a few seconds, then let the joint cool before moving it.

Typical Welding Times

Follow your pipe maker's chart; times are longer in cold or windy conditions.

Pipes, Fittings and Tools

Some photos are reference images of the product type, used under open licences. Image credits are on each product page.

Names and sizes of every fitting: PPR fittings names and sizes; full list: PPR price list. Comparing materials? See PPR vs PVC vs HDPE.

Supports and Pressure Testing

• Clip horizontal pipes about every 60–80 cm (closer for hot water).
• Leave room for expansion on long hot-water runs.
• Fill the system, bleed air, and pressure-test for at least 30 minutes before plastering over.
• Check every joint for weeping.

Worked Example: Kitchen and Bathroom

A typical small bathroom plus kitchen run from a tank might use 6–8 lengths of 20 mm pipe, a gate valve (KSh 520) at the tank outlet, elbows at every bend and couplers at joins. Count every bend on your drawing and buy a few spares: they cost about KSh 25 each.

Common Mistakes to Avoid

• Twisting the joint while pushing together.
• Over-heating so the pipe bore narrows.
• Cutting with a hacksaw (rough, angled cuts).
• Not marking socket depth.
• Closing walls before a pressure test.

Not sure which one fits? Send us your details on WhatsApp or through the product page and we will help you choose.

Frequently Asked Questions

How do you join PPR pipes?

By heat welding pipe and fitting together on a PPR welding machine.

What temperature is used for PPR welding?

About 260 °C.

How long do you heat a 20 mm PPR pipe?

Around 5 seconds, then join and let it cool.

Can PPR be used for hot water?

Yes, PPR is rated for hot and cold water; support hot runs more closely.

How much is PPR pipe in Kenya?

20 mm PPR pipe is KSh 380 on Buy More Mall.

Do I need a special cutter for PPR?

A PPR cutter gives square cuts that weld properly; it costs from KSh 400.

Prices shown are regular prices on Buy More Mall. Many products are currently on offer, so open the product page to see today's price.

Related Guides

• PPR Fittings Names and Sizes
• Cost of Plumbing a House
• How to Install a Water Tank