McAlpine ST28M Compression reducer 1 1/2" x 1 1/4"

McAlpine ST28M Compression Reducer 1½" x 1¼"

Professional Waste Pipe Reducer for Seamless Plumbing

The McAlpine ST28M Compression Reducer (1½" x 1¼") is an essential component for any plumbing project that involves connecting different waste pipe sizes. Manufactured to high standards by McAlpine, this reducer fitting provides a quick and reliable solution for adapting a 1½-inch waste pipe to a 1¼-inch connection—ideal for basins, baths, and kitchen sinks.

Engineered from strong, chemical-resistant polypropylene, it delivers a watertight seal without the need for solvent cement or adhesives, making it perfect for both DIYers and professionals looking for a clean, tool-free solution.

Key Features

• Product Code: ST28M

• Brand: McAlpine

• Connection Sizes: 1½" (male) to 1¼" (female)

• Material: Polypropylene (PP)

• Installation Type: Compression fitting (tool-free)

• Colour: White

• Application: Domestic and commercial waste systems

• WRAS Approved: Yes

Why This McAlpine Reducer Is a Must-Have

Whether you're upgrading a bathroom suite or repairing existing plumbing, this compression reducer offers:

• Effortless Installation – No solvent weld or glue needed

• Leak-Free Connection – Compression seal ensures watertight results

• Reusability – Can be removed and reused without damaging pipes

• Versatile Use – Suitable for sinks, basins, baths, and more

• Compatible with various waste pipe brands and systems

It’s a particularly useful fitting when retrofitting new sinks into older plumbing systems where pipe diameters may not match.

How to Use the ST28M

1. Cut and prepare your 1½" and 1¼" plastic waste pipes.

2. Slide the pipes into the reducer’s openings.

3. Hand-tighten the compression nuts—no tools or sealants needed.

4. Test for leaks before finalising installation.

This simple process makes the McAlpine ST28M a popular choice for time-sensitive jobs or where solvent bonding isn’t practical.

Designed for Kitchens and Bathrooms

Perfect for installations in domestic kitchens and bathrooms, this reducer connects larger 1½" pipework—common for kitchen sinks or baths—to 1¼" pipework found in basins or other sanitaryware. It can be used as part of both new installations and repairs.

Pair With Compatible Categories

To complete your plumbing project efficiently, you may want to explore:

• Our full Plastics Waste Pipe range

• Quality Pipe Fittings for extending or adapting pipe systems

• Durable Valves and Flexible Hoses to enhance flow control and flexibility

• Other Waste Fittings to match your installation requirements

Frequently Asked Questions (FAQs)

Q: Can I use this with metal waste pipes?
A: No, this reducer is designed for plastic pipe systems only.

Q: Do I need tools to install this reducer?
A: No, this is a hand-tightened compression fitting—no tools required.

Q: Is it reusable?
A: Yes, it can be removed, cleaned, and reused multiple times.

Q: Is it compatible with solvent weld pipe?
A: Yes, it can be connected to both push-fit and solvent weld plastic waste systems.

McAlpine – Industry-Leading Plumbing Brand

McAlpine is a UK-based manufacturer known for reliable, innovative plumbing solutions. Their compression waste fittings—like the ST28M—are WRAS approved and designed for performance, safety, and ease of use. Trusted by plumbers and builders nationwide, McAlpine continues to lead the market in plumbing connectivity solutions.

Technical Specification Table

Shop Now at Wise Guys DIY

You can buy the McAlpine ST28M Compression Reducer 1½" x 1¼" directly from Wise Guys DIY—your trusted supplier of plumbing, heating, and building supplies.

Need more plumbing solutions? Browse our Plumbing & Heating category for everything from valves to waste fittings.