How to fit a toilet

It's not too difficult to replace your old toilet, as long as you can connect it to an existing branch of the soil pipe. But if you want to add a new toilet in another part of your home, you should get a professional plumber to connect into the main soil pipe. You can cut your water usage significantly by fitting a dual flush toilet mechanism.

There are loads of different toilet designs to choose from that suit every style of interior. Close-coupled cisterns sit directly on top of the pan and are a very popular modern design. Always unpack and carefully inspect your new toilet or suite before you rip out your old fittings. After all, you don't want to discover a fault, crack or missing part when your bathroom is out of action.

Safety first

An electronic detector will highlight any hidden pipes and cables under the floor and in the wall. This is an important thing to do prior to drilling to prevent an accident.

1. Assemble the flush mechanism

Following the manufacturer's instructions, assemble and insert the flush mechanism. Make sure you include the rubber sealing rings where necessary. Place the large rubber gasket into the flush entrance of the pan.

Person lining up the connecting bolts on a toilet cistern to the holes on the toilet pan to fit them together.

2. Fit the cistern to the pan

Insert the long fixing bolts through the holes in the cistern, using the rubber and large metal washers supplied. Lift the cistern onto the pan so the connecting bolts fit through the holes. The threaded section of the flush mechanism should go through the rubber gasket on the flush entrance of the pan.

Fit washers to the connecting bolts, and tighten the wing nuts. Make sure you fit these securely - but don't over-tighten them.

Person using a screwdriver to screw retaining screws through the base of a toilet pan into the floor.

3. Secure the toilet to the floor

Next, check there are no pipes or cables beneath the fixing points. Put the toilet in place, and slide the pan outlet into the flexible connector that's attached to the soil pipe (a little silicone grease will ease it on). Then drill some pilot holes into the floor at the fixing points. If it's a solid floor, you'll need to make the holes with a hammer-action drill and plug them.

Push plastic protective inserts through the holes in the base of the pan, and insert the retaining screws through and into the floor. If the cistern has fixing holes in the back, attach it to the wall by drilling and plugging. Remember to add rubber washers before you tighten the nuts.

Connecting a toilet cistern to the copper water supply pipe using a straight push fit connector.

4. Connect to the water supply

Connect the supply pipe for the cold water feed, using a push-fit tap connector.

Using a screwdriver to secure a toilet seat to a toilet pan with a screw.

5. Fit the toilet seat

Fit the hinge assembly to the seat, following the manufacturer's instructions. Connect the seat to the pan by securing through the holes at the back, using the screws supplied. Then adjust it to sit in the correct position.

A valve-operated flush mechanism is quite easy to install and also can replace your existing flush . As flush mechanisms do vary between designs and can be controlled by either a handle or button, always read the manufacturer's assembly instructions. Shut off the water supply and flush the toilet to empty the cistern before you start.

Person lifting a ball valve flush mechanism out of the top of a toilet cistern.

1. Remove the existing flush mechanism

Lift off the cistern lid and take out the ball valve, handle and existing flush mechanism. Clear any loose dirt from the tank, then unscrew the wingnuts from under the pan and remove the existing filling valve. Lay a dust sheet for protection over the toilet lid and rest the cistern on top.

Person holding a toilet flush button on the outside of the toilet cistern with one hand, whilst clipping the flush cable control to the back of the button inside the toilet cistern.

2. Fit the valve operated flush mechanism

Clip the flush cable control to the ball float mechanism, and connect this to the base of the cistern using the backnut and grommet supplied. Next, adjust the filter restrictor according to whether the water supply is at mains pressure or supplied from a tank. Remember to follow the manufacturer's instructions when you do this. Then insert the filter restrictor into the threaded tail of the filling valve, and attach the filling valve to the inlet pipe using the backnut and washer supplied.

Clip the flush cable control to the push button, and use the backnut supplied to secure the push button.

Using an adjustable spanner to tighten a nut between two sections of copper pipe underneath a toilet cistern.

3. Reconnect the water

Put the cistern back in place and re-attach it to the toilet pan. Then re-attach the tap connector that links the water inlet pipe with the filling valve.