Skill Level: Intermediate
In most modern homes the bathroom light is operated by a pull cord switch, but some older bathrooms do still have the older wall mounted type. However, this type of switch can be dangerous if an electrical wiring fault makes the switch live and it is touched by someone using the bath or shower.
It isn’t actually such a big job to replace an older wall mounted switch with a new pull cord type. As always with electricity, the byword is safety! Never start working on electrical fittings and fixtures without first turning the power off at the mains.
You don’t need a huge amount of tools to do this little job, but do make sure they are the right tools. Making do with whatever comes to hand is responsible for many a failed DIY project or repair job, so always buy the best tools you can, they’ll last for years if you look after them and use them properly.
First things first, turn the power off, and remove the fuse of the circuit you are working on.
Unscrew the fastening screws of the old wall mounted switch plate, and disconnect all wiring connections. Trace the exact path of the cable where it runs up to ceiling height - an electrical wiring detector is perfect for this purpose. When you have established the line of the cable, use a club hammer and cold chisel or bolster to chip out the top 120 – 150mm of plaster below the ceiling ( to gain access to the cable) and cut the cable leaving about 75mm or so below ceiling height. The rest can stay buried in the wall. It just remains then to be pulled up through the ceiling from the roof space, or from a lifted floorboard from the floor above.
If the old wiring is protected by conduit within the plastered wall, then there is no need for the club hammer and chisel; simply go into the roof space or next floor – lift a floorboard, and pull the cable up, remember to disconnect from the wall switch first.
If you are using a hammer and chisel to chip away the wall plaster, then make sure you wear safety spectacles or goggles. Plaster isn’t as hard as concrete or mortar, so you don’t have to exert too much force to remove it.
Take the pull cord switch fitting
Take the pull cord switch fitting and undo the screws holding the switch pull to its base, then push out and remove the stamped knock-out cable hole in the base of the base box.
The next thing to do is fix the base box securely to the ceiling (preferably in the timber joists above) using wood screws.
Next, feed the cable through the back of the switch box. Before making final electrical connections, make good any plaster work around the switch and ceiling. Also, any making good where you excavated the wall.
Making the electrical connections
If you are using existing cabling there may or may not be an earth conductor. So check first!
There are two wires, apart from the earth, in a pull cord switch; a red, and a black; and it does not matter into which terminal (behind the switch) you fit these wires.
When the wiring is connected, it remains only to fix the pull cord switch to the base; replace the fuse – and switch on.
Tools you will need:
Faithfull 1.8Kg / 4Lb Fibreglass Handled Club Hammer -
Roughneck 300mm x 25mm Cold Chisel & Grip -
Rapitest WPP123 Wire-Pipe and Power Detector -