How to install a wall-hung toilet

Choosing a wall-hung toilet allows you to combine style, comfort and hygiene. In terms of style, the toilet pan is the only part of the unit on show. The height of the seat can be modified for added comfort. These toilets are also far quieter than traditional models as the fill valve tends to make less noise. The fact that wall-hung toilets don't have a base makes them more hygienic and easier to clean. What's more, as the cistern is covered up, there is less chance of bacteria growth.

That being said, installing a wall-hung toilet can be more complicated and expensive than fitting traditional models. Nevertheless, these toilets offer a number of advantages, making them an increasingly popular choice in new builds and home renovations. This is mainly due to the fact that wall-hung toilets are designed to fit seamlessly into your bathroom. 

2 hours (not including time taken to conceal frame)

Installation time for replacing an old unit

3 hours or more (depending on existing toilet set-up and choice of frame covering)

When you start watching the Grohe Installation Guide below, you will notice that the handyman is installing a very specific type of wall-hung toilet: a self-supporting model on a frame. While the process for installing wall-hung toilets won't change much between brands, some parts and measurements may vary. Factors that may differ include the finishing features or how easy the unit is to install (fixing the feet, mounting brackets, etc.).

It may surprise you to know that self-supporting wall-hung toilets are actually easier and more convenient to install when renovating a bathroom –although these are slightly more expensive to purchase.

Replacing an older unit with a wall-hung toilet will be more challenging as you will need to work around the original toilet position and bathroom layout. In these cases, the aim is to install the new toilet as close as possible to where the previous unit was. 

Cut off the water supply at the valve.

If you are dealing with an old unit, empty the cistern and remove the toilet by dismantling the cistern and the toilet pan, in that order. Adjust the water supply line as needed: resize the copper pipe, clean it up by sanding down the end and insert a compression fitting. 

Cut the waste pipe so it is close to the ground (+/- 5 mm) and insert a waste adaptor into the pipe. Sand down the ends of both parts and coat them with PVC glue before connecting them. 

If necessary, block the pipe temporarily to avoid any unpleasant odours.

Read the assembly instructions for the new wall-hung toilet and get your supplies ready. Gather all the assembly screws alongside their corresponding parts.

Assemble the vertical upright bars and horizontal support bars on the ground and screw them together loosely by hand. Then use an open-ended or ratchet spanner to tighten. 

Place the fixing mounts onto the cistern and slide the flush pipe into place. Make sure to insert the seals and to push all pipes and parts into a fully locked position. 

Draw a vertical line along the centre of the water pipe for positioning the toilet pan and mark points to indicate the height of the frame. 
 
Using a spirit level, draw the line high enough to incorporate the position of the brackets.

Using a tape measure, start by drawing a line at a height of 40 cm for the toilet pan (this height can vary from 40-45 cm according to your needs). Next, draw a line at 1 metre and mark it as (A), then draw another line at 1.08 metres and mark this as (B). These will be used to map out the position of the wall brackets (follow the positions recommended by the manufacturer). 

Check that your horizontal lines are level using a spirit level from the left to the right of the vertical line you have drawn from the centre of the waste pipe. 

Position the frame and check the measurements and placement of the water supply line and waste pipe, as well as the space between the frame and the wall (this will vary according to frame depth). If necessary, use a waste pipe adaptor.

Mark out the location of the feet on the floor.

Set the pan connector into place. Grease and insert an adaptor if needed.

Check the height of both the pipe (measure and cut if necessary) and the frame to make sure it matches up with the markings. 

Use a drill fitted with the correct drill bit to make holes where the wall brackets and the feet will go and insert the appropriate fixing plugs.

Make sure to remove any dust from the holes so the fixings can secure firmly. Position the frame in line with the 'A' mark (the first line you drew).

 

Remove the transport bracket by pulling on its handle. Be careful to not damage the mechanism or the pipe in doing so. 

Connect the cold water connection to the shut-off valve then attach the water inlet hose and corresponding seals. 

You can position the water supply line beforehand to face the mechanism. 

Be sure to check that the connections are watertight by turning the water back on (make sure the valve is closed at this point). 

Next, check that the water supply works by opening the valve, making sure you have a bucket in place to catch the water.

Connect the inlet hose to the flush mechanism and position the flush plate bracket. 

Insert the flush plate bracket by lightly tapping several times.

Install the boards or unit used to conceal the frame (this might also be referred to as cladding) or build a stud wall using plasterboard.

Mark the cut-outs that will accommodate the different features (waste pipe, toilet pan and flush pipe) using the corresponding cutting templates. 

Mark out and cut panels to cover the frame's sides before securing them in place using the fixings provided. Most models offer a cutting template for the furniture unit used to conceal the cistern. 

Cut out the various holes with a jigsaw. 

Assemble the flush pipe and waste pipe and connect them into position in the pan, making sure they are fully clipped in. 

Be sure to avoid damaging the seal when inserting them – this will be easier if you use a twisting motion. 

Use a pen to mark where the pipes extend past the edge of the toilet pan (it's best to use a felt-tip marker for this). 

Remove the pipes from the toilet pan and insert them into position in the frame, making sure they are inserted fully into the slot. Mark the position of the pipes where they emerge from the frame. 

Carry this measurement over to the ends of the pipes. Measure the space between the two marks, adding 5 mm, then cut off the male end using a metal saw. 

Use a support stand for increased safety. 

Smooth down the edges using a file or sandpaper for a better fit and insert them into the support frame. Be sure to remove any leftover residue. 

Insert the threaded rods into the fixing frame, letting them emerge as per the manufacturer's recommendations (usually 6 cm). Spread silicone grease or soapy water onto the flush pipe to make it easier to insert into the pan. Position the pan in line with the pipes and threaded rods and push it firmly into place. You should also apply silicone grease onto the pan where the connections will go to make insertion easier. 

Insert the plastic guides then secure the pan using the provided nuts and washers. Loosely tighten all parts, making sure that everything is level, then add the nut covers.

Screw everything into place approximately before tightening all the way.

Cut out the mounting bracket for the flush plate with a cutter so it lies flush with the frame cover, making sure to cut straight using a continuous motion. 

Turn on the water supply and position the mounting bracket with the plastic springs facing downwards, then secure using screws. Use a Phillips head or flat screwdriver depending on the screw drive. 

Fit the mechanism into the bracket, connect the water supply line and insert the flush plate starting from the bottom of the panel. 

Apply light pressure to the top and corners of the plate to make sure it is correctly clipped in.

Test the flush mechanism to make sure it is working correctly.

For DIY enthusiasts or anyone undergoing a full bathroom renovation, follow the links below for bathroom-related advice from our editors and more helpful guides: