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How to fit a shower

When you're choosing a shower, it's important to pick one that's compatible with your home's plumbing system, and they're put together in different ways too. Use our guide to help fit your new shower.


If you have a gravity-fed system (with a hot water cylinder and a cold water storage cistern in your loft), you have the most options. You could go for a mixer shower with or without a pump, a power shower or an electric shower.

If you've got a combination boiler or your cold water comes directly off the mains, your options are a mixer shower or an electric shower. This is because a combi boiler or mains supply does not allow you to fix a pump.


Whether your thermostatic mixer shower has got a pump or not, you can supply it via branch pipes from your hot and cold plumbing system. Try to join them as near as possible to your cold and hot water tanks, and run them to the shower position and through the wall.

The hot and cold water pressure in a gravity-fed system is determined by the height of the cold water tank above your shower.

Without a pump, you need at least one metre between the bottom of your tank and the shower head to give you a decent flow rate and pressure. If you don't have enough difference in height, you'll either need to raise your cold water tank or fit a pump in your system.

NB: Our Homefit service will no longer be available from 9 July 2018. Any existing orders will be honoured until 14 December 2018.

 

Safety precautions

  • Ensure your mixer is installed, commissioned, operated and maintained in accordance with the manufacturer’s recommendations.
  • Read the manufacturer's instructions carefully.
  • The shower unit must not be fitted where it may be exposed to freezing conditions.

 

1. Prepare the area

Check the contents to make sure all parts are present. Before starting the mixer installation, make sure all the openings on the valve are carefully covered to prevent any debris getting in while working on the supply pipework.
Be sure of the type of wall you have and whether the shower valve is suitable.

2. Install the pipework

When you have decided on the position of the shower and direction of pipe entry (for example rising, falling or rear entry), complete the pipework to the shower area. The hot and cold water pipes should be securely attached within the wall or panel to support the valve and prevent movement after installation.

3. Turn on the water

Caution! Make sure that the compression olives are fitted and all pipework is flushed through before connecting to the shower valve.

Turn on the water to check for leaks.

Install the outlet fittings (refer to your manufacturer's installation guide for specific instructions).

Adding a pump

Adding a booster pump to your thermostatic mixer shower can more than double the flow rate. You can hide the pump under a bath or tuck it away in an airing cupboard or loft, so you won't see (although you might hear it in action). But remember that you can't connect a pump to a combi boiler or a cold water supply coming straight off the mains. And to get the most out of it, you might have to install a bigger hot water cylinder.


Try and set your rail high enough for the tallest person in your house - but not so low that your shower head dangles any less than 25mm from the spill-over level of the shower tray, bath or nearby basin. If it's too low, used water might go back into your household supply.

Person marking the fixing holes for a shower rail bracket on bathroom tiles with a pencil.Person marking the fixing holes for a shower rail bracket on bathroom tiles with a pencil.Person marking the fixing holes for a shower rail bracket on bathroom tiles with a pencil.Person marking the fixing holes for a shower rail bracket on bathroom tiles with a pencil.

1. Mark the fixing holes

Fit the lever and holder to the slider rail. Then put the brackets on the ends of the rail and mark the position of the fixing hole for the lowest bracket.

Person using a drill to drill a hole in a tiled bathroom wall.Person using a drill to drill a hole in a tiled bathroom wall.Person using a drill to drill a hole in a tiled bathroom wall.Person using a drill to drill a hole in a tiled bathroom wall.

2. Drill the hole

First, use an electronic detector to check carefully that there are no hidden pipes or cables. Then drill where you've marked the position of the lower bracket. Pop in a wall plug and squeeze a spot of sanitary silicone sealant onto it.

Person using a screwdriver to secure the bracket for a shower slider rail to a bathroom wall.Person using a screwdriver to secure the bracket for a shower slider rail to a bathroom wall.Person using a screwdriver to secure the bracket for a shower slider rail to a bathroom wall.Person using a screwdriver to secure the bracket for a shower slider rail to a bathroom wall.

3. Fit the bracket

Remove the slider rail from the brackets and fix the bottom bracket to the bottom hole, using the screw supplied. To find the position of the top fixing hole, just put the rail back onto the bottom bracket and put the other mounting bracket on the top of the rail. Use a spirit level to check it's vertical, and mark the top fixing hole on the wall.

Pushing the bracket cover for a bathroom shower rail upwards onto the shower rail bracket.Pushing the bracket cover for a bathroom shower rail upwards onto the shower rail bracket.Pushing the bracket cover for a bathroom shower rail upwards onto the shower rail bracket.Pushing the bracket cover for a bathroom shower rail upwards onto the shower rail bracket.

4. Fit the top bracket

Take the rail off, and drill and plug the wall as you did before. Then screw the top bracket in with the rail in place. Finally, fit bracket covers onto the top and bottom brackets.


When the waste pipework is ready, you can fit your shower tray and connect its waste outlet to the trap. But make sure you read the manufacturer's installation instructions, as different designs might need to be installed in slightly different ways.

Person fitting a waste outlet to the hole in a shower tray which has a bead of silicone around the edge.Person fitting a waste outlet to the hole in a shower tray which has a bead of silicone around the edge.Person fitting a waste outlet to the hole in a shower tray which has a bead of silicone around the edge.Person fitting a waste outlet to the hole in a shower tray which has a bead of silicone around the edge.

1. Fit the waste

Hold the tray on its side and run a bead of sanitary silicone sealant around the waste hole.

Put the waste outlet into the hole so it goes into the sealant. Make sure you've fitted any washers that were supplied, and use an adjustable spanner to screw on the locking nut. Then you can fit the trap to the waste outlet.

Person holding a spirit level over the top of a shower tray which has been installed on a bed of mortar.Person holding a spirit level over the top of a shower tray which has been installed on a bed of mortar.Person holding a spirit level over the top of a shower tray which has been installed on a bed of mortar.Person holding a spirit level over the top of a shower tray which has been installed on a bed of mortar.

2. Install the tray

Put on some protective gloves and mix the mortar. Take a trowel to put a thin layer on the floor where your tray will go, then put it in place.

Bed the tray down into the mortar, using a spirit level to check it isn't sloping. If you can't get it exactly level, you might need to lift up the tray and adjust the mortar. Tidy the edges and remove any excess mortar with the trowel. Then finish the job by opening the floor hatch and connecting the trap to the waste pipe.


You can buy a shower enclosure as part of a new bathroom or add one to your existing suite. They can fit either into the corner of a room or against a flat wall. There are a variety of door styles for your enclosure such as hinged or pivoted, and for a great space saving option, there are folding and sliding doors.

Before you fit your enclosure, you'll need to have your shower tray, mixer valve, pipework and tiling in place. The example below shows a corner enclosure with curved sliding doors - but there are lots of designs available and each is installed in a slightly different way, so make sure you read the manufacturer's instructions. With any enclosure, it's essential that the wall and tray are fully waterproof and the uprights of the frame are vertical.

The waste pipes and trap

Before choosing your shower enclosure, you'll need to work out how you're going to run the drainage pipes, and check how much height you need under the tray for the pipework. You might be able to cut a hole in the floor to fit the waste pipe. If so, you'll also need to make an access hatch. To do this, you can either extend the hole for the waste trap beyond where the outside edge of the shower tray will be, or make a separate hatch nearby within reach of the trap. If your floor is solid, or you can't get enough of a fall for drainage under a suspended floor, you have a couple of options. You could go for an enclosure with a step up to the tray, or raise your tray above floor level by fitting it on a plinth. If you don't have enough space under the shower tray to fit a shallow P-trap, you could fit a compact trap. This is specially designed to give you the necessary water seal, while being shallow enough to fit under most modern shower trays. Its removable grid also makes it easy to clean.

Person lining up a shower enclosure door to rails on a shower enclosure frame.Person lining up a shower enclosure door to rails on a shower enclosure frame.Person lining up a shower enclosure door to rails on a shower enclosure frame.Person lining up a shower enclosure door to rails on a shower enclosure frame.

1. Assemble the shower enclosure

Lay the two fixed side panels flat, and put some generous beads of sanitary silicone sealant into the curved channels at the top and bottom. Then attach the head and sill rails with the screws provided - taking care not to over-tighten them.

Slide the plastic guide tracks into the head and sill rails. Use a junior hacksaw to shorten the plastic guide tracks if they're too long. Push two door stops into the guide track in the head and sill rails. You can move them into the middle, but don't fix them yet.

Stand the shower enclosure upright and slide the curved sliding doors into the head and sill rails, making sure that the doors are the right way around. Then put another doorstop into both the head and sill rails.

Person using a pencil to mark where holes for a shower enclosure wall channel should be drilled.Person using a pencil to mark where holes for a shower enclosure wall channel should be drilled.Person using a pencil to mark where holes for a shower enclosure wall channel should be drilled.Person using a pencil to mark where holes for a shower enclosure wall channel should be drilled.

2. Fit the wall channels

Attach the wall channels to each side of the enclosure, and stand it on the tray - checking it's vertical with a spirit level. Then, from the inside of the enclosure, use a chinagraph pencil to mark the position for the fixing holes through the pre-drilled holes in the wall channels.

Take off the enclosure, and check for hidden pipes and cables behind the fixing positions with an electronic detector. If all is clear, drill fixing holes in the marked positions. Push wall-plugs into the holes, making sure they go in beyond the depth of the tile.

Running a bead of silicone sealant along the wall channel of a shower enclosure.Running a bead of silicone sealant along the wall channel of a shower enclosure.Running a bead of silicone sealant along the wall channel of a shower enclosure.Running a bead of silicone sealant along the wall channel of a shower enclosure.

3. Seal the wall channels

Run an unbroken bead of sanitary silicone sealant down both wall channels. Then put the enclosure onto the base and screw in the fixing screws. Wipe off any excess sealant and check the instructions to make any final adjustments to the sliding doors.

4. Fit the rest of the enclosure

From the inside, drill through the holes in the wall channels and into the frame. Put in the screws provided and cover the heads with screw caps. Drill through the plastic track and inner head channel, and then screw the doorstops into place.

Using a sealant gun to run a bead of silicone sealant around the edge of a shower tray where it meets a tiled wall.Using a sealant gun to run a bead of silicone sealant around the edge of a shower tray where it meets a tiled wall.Using a sealant gun to run a bead of silicone sealant around the edge of a shower tray where it meets a tiled wall.Using a sealant gun to run a bead of silicone sealant around the edge of a shower tray where it meets a tiled wall.

5. Seal the enclosure

Seal the join between the tray and the tiled wall with a continuous bead of sanitary silicone sealant. Do the same around the outside edges of the enclosure.


For your safety, these products must be installed in accordance with local Building Regulations. If in any doubt, or where required by the law, consult a competent person who is registered with an electrical certification scheme. Further information is available online or from your local authority.

All new and modified installations must comply with the latest IEE Wiring Regulations. Either use an electrician registered with the self certification scheme prescribed in the regulations, or if you carry out the work yourself, you must notify your Local Authority Buidling Control Department to get your work inspected and tested.