Electric Shower Installation in Slough
Replacing a tired shower or fitting a more powerful one? I do the electrical side properly, so it runs at full power and stays safe around water.
An electric shower is one of the hungriest things in the house. It heats water on demand, so it draws a serious amount of current the second you switch it on, more than most sockets or lights ever will. That's exactly why it needs its own dedicated circuit running straight back to the fuse box, and why the cable and the fuse or MCB protecting it have to match the shower you're actually fitting.
There are really two jobs here. A like-for-like replacement is swapping a dead shower for a new one of the same rating on a circuit that's already sound, which is usually quick. A new circuit is where there's no shower there yet, or the old wiring isn't up to the job, so I run fresh cable from the consumer unit. The one that catches people out is wanting a bigger, more powerful shower on the old cable.
Why the kW rating matters
Showers come in different powers, commonly 8.5kW, 9.5kW and 10.5kW. The higher the kW, the hotter and stronger the flow, but the more current it pulls. Jump from an 8.5 to a 10.5 and the cable has to carry noticeably more, which often means a thicker cable and the right MCB to protect it. A lot of the older housing stock around here, the 1930s semis in Cippenham, the older terraces in Langley, was wired decades ago for much smaller loads. It's really common to find cable that was fine for the old shower but is undersized for a modern high-powered one. Fit the bigger shower on cable that can't take it and you get a circuit running warm, tripping, or worse. I check first, then fit.
Doing it safely in a bathroom
A shower circuit has to be isolated so it can be switched off properly, that's the pull-cord switch you see on the ceiling, or a suitable isolator outside the bathroom. It needs to be on RCD protection, which matters more in a wet room than anywhere else in the house, because it cuts the power in a fraction of a second if there's a fault to earth. I also check the bonding, the connections that keep everything at the same safe electrical level around the bath and basin, because bathrooms have their own zone rules under the wiring regulations.
Before I touch a higher-powered shower I take a look at your consumer unit too. Adding a hungry new circuit only works if the board has a spare way and enough capacity. Sometimes the sensible answer is a shower swap today and a board upgrade down the line, and I'll be honest about which you actually need.
One last thing people ask: plumber or electrician? For an electric shower it's usually both. I do all the electrical side, the circuit, the isolation and the connection. The plumbing and the shower unit itself is a plumber's trade. I'm happy to coordinate so you're not stuck managing two lots of trades yourself.
What I Cover
- Like-for-like electric shower replacements
- New dedicated shower circuits from the consumer unit
- Upgrading to a higher kW shower (8.5, 9.5, 10.5kW)
- Correct cable sizing for the shower rating
- Pull-cord switches and proper isolation
- RCD protection and bathroom bonding checks
How The Job Goes
- 1 Check your consumer unit and existing circuit
- 2 Confirm the cable and MCB suit the shower's kW rating
- 3 Free, honest quote with the work explained plainly
- 4 Isolate, install and connect the shower safely
- 5 Test the circuit and RCD, then certify the work
- 6 Show you how it runs and hand over the paperwork
Why It's Worth Doing Right
Right kW, Right Cable
I size the circuit to the shower so it runs at full power without overheating.
RCD Protected
Every shower circuit is on RCD protection, which matters most in a wet room.
Bathroom Safe
Bonding and zone rules checked so the electrics are safe around water.
Done In A Day
Most straightforward swaps are a few hours, not a lost weekend.
Common Questions
Can I fit a bigger kW shower on my existing cable?
Not always. A 10.5kW shower pulls a lot more current than an old 8.5kW one, and older cable often can't carry it safely. Plenty of the 1930s semis around Cippenham and Langley were wired for much smaller loads, so the cable and the MCB both need checking before I fit anything bigger. If the cable's too thin I'll tell you straight and run a new one rather than push a shower it can't handle.
My electric shower keeps tripping the fuse box, what's wrong?
Usually it's the shower's heating element breaking down and leaking to earth, which trips the RCD, or a loose connection getting warm. Sometimes it's an undersized MCB nuisance-tripping under load. It's not something to keep resetting and ignoring, it's the safety device doing its job. I'll test the circuit and the shower and find the actual cause rather than guess.
How long does an electric shower installation take?
A like-for-like replacement where the cable and circuit are already fine is often just a few hours. Running a brand new dedicated circuit back to the consumer unit, or upgrading to a higher-powered shower that needs new cable, takes longer. I'll give you a clear timeline when I quote so there are no surprises.
Do I need a plumber or an electrician for a new shower?
For an electric shower you usually need both. I handle the electrical side, the dedicated circuit, the isolation and the connection. The water side, the pipework and the shower unit itself, is a plumber's job. I'm happy to coordinate so it's not left to you to juggle two trades.
How much does an electric shower installation cost?
It depends on the job. A simple swap on a sound existing circuit is very different from running new cable across the house or upgrading a full consumer unit to make room for the shower. I don't quote blind, I come and look, then give you a free no-obligation price with everything explained.