If you've ever heard a loud banging or knocking noise when you turn off a tap or your washing machine finishes a cycle, you're not imagining things — that's water hammer. And it’s more than just annoying. Left unchecked, it can damage your plumbing over time.

Let’s break down what causes it, how to prevent it, and what we see in homes across Exeter.

What Is Water Hammer?

Water hammer happens when water flowing through your pipes suddenly stops or changes direction. This creates a shockwave that can cause your pipes to vibrate or bang against walls, joists or other pipes. It’s most common with fast-acting valves like those on washing machines and dishwashers.

Over time, this constant pressure can wear down pipe joints, cause leaks, or even lead to burst pipes in more extreme cases.

How to Prevent Water Hammer

Here are the most effective solutions we recommend:

1. Install Water Hammer Arrestors

These are mechanical devices that absorb the shock of moving water. They're commonly fitted to appliances like washing machines and dishwashers. If you’re having a new appliance installed, it's worth asking your installer to check for these.

2. Secure Loose Pipework

Sometimes the issue is simply that pipes aren’t clipped properly. If they’re allowed to move, the sound can be much worse. We often find this in older properties around Exeter where pipework has been modified over time.

3. Reduce Water Pressure

High water pressure can make water hammer worse. A plumber can test your incoming pressure and fit a pressure-reducing valve (PRV) if needed. Ideally, you want your pressure around 3 bar or below.

4. Replace Old Valves

Worn-out or faulty valves can close too abruptly. In some cases, swapping old isolation valves for modern, quarter-turn ones can ease the issue.

Can You Fix It Yourself?

If you're confident and the problem is minor (like a loose pipe or no arrestors on an appliance), you might be able to handle it. But if it’s ongoing, or if you're seeing signs of leaks or pipe movement, it's best to get a professional in.

At EPM, we’ve helped plenty of homeowners in Exeter deal with noisy pipework. Sometimes it’s a quick fix, sometimes it's a bit more involved — but we’ll always give you the honest answer.

Final Thoughts

Water hammer might seem like a harmless nuisance, but over time it can cost you — whether in repairs, leaks, or long-term wear on your plumbing system. If you're dealing with banging pipes, give us a call. We’ll come take a look and let you know exactly what’s going on.