How to Measure Pipe Centres for a Towel Radiator (UK Guide)

If you're installing or replacing a towel radiator, knowing how to measure pipe centres correctly is essential. Accurate measurements ensure your new radiator lines up perfectly with existing pipework—saving you from costly plumbing adjustments.

In this guide, you’ll learn exactly how to measure pipe centres, avoid common mistakes, and choose the right radiator size.

---

What Are Pipe Centres?

Pipe centres refer to the distance between the centre of one pipe and the centre of the other pipe that connect to your radiator valves.

This measurement is usually given in millimetres (mm) and is a key specification when buying a towel radiator.

👉 Important:
Pipe centres are NOT the same as radiator width

---

Why Pipe Centre Measurement Matters

Getting this measurement right helps you:

• ✅ Ensure your towel radiator fits existing pipework
• ✅ Avoid moving pipes or lifting flooring
• ✅ Save time and installation costs
• ✅ Achieve a neat, professional finish

---

Tools You’ll Need

• Tape measure (metric)
• Notepad or phone
• Optional: spirit level

---

How to Measure Pipe Centres (Step-by-Step)

1. Identify the Pipe Positions

Locate the two pipes that will connect to your radiator. These may come from:

• The floor (vertical pipes)
• The wall (horizontal pipes)

---

2. Measure Centre-to-Centre

The most accurate method is:

• Measure from the centre of one pipe to the centre of the other

If the centres are visible, simply place your tape measure between them.

---

3. Measure Edge-to-Edge (Alternative Method)

If you can’t see the centre of the pipes:

• Measure from outside edge to outside edge
• Add the pipe diameter

---

4. Measure Between Valves (If Installed)

If you already have radiator valves fitted:

• Measure between the centre of each valve inlet

This is often more accurate when replacing an existing radiator.

---

Standard Pipe Centre Sizes (UK)

Most UK homes use:

• 15 mm pipes
• Common towel radiator pipe centres:
  • 400 mm
  • 450 mm
  • 500 mm
  • 600 mm

Always measure your own setup to confirm.

---

Common Mistakes to Avoid

• ❌ Confusing radiator width with pipe centres
• ❌ Measuring from edge to edge without adding pipe diameter
• ❌ Ignoring valve spacing
• ❌ Not allowing for small adjustment tolerance

---

Pro Tips for a Perfect Fit

• Leave a tolerance of ±5 mm (valves allow slight adjustment)
• Check whether your radiator uses:
  • Side connections (standard)
  • Central connections (modern designs)
• Measure twice before buying

---

FAQs

Q: Are pipe centres always smaller than radiator width?
Yes, the pipe centres are slightly less than the overall width.

Q: What if my measurement doesn’t match standard sizes?
You can use adjustable valves or pipe extensions—or choose a radiator with flexible connections.

Q: Do I need a plumber?
Not always, but if pipes need moving, it’s best to hire a professional.

---

Conclusion

Measuring pipe centres for a towel radiator is simple but critical. With the right approach, you can confidently choose a radiator that fits your existing pipework perfectly—no stress, no surprises.