How to Fit Bathroom Wall Panels Around a Wall-Hung Toilet

Panelling the wall containing the wall hung toilet is very different to just panelling a plain wall. Whilst they appear floating there is a steel framework, hidden cistern and boxed section in the wall. The panels need to cover the box in an even manner leaving a clean flush plate. You also need to ensure they are watertight where they meet the floor and pan.

This guide will walk you through each step of fitting, including checking what is behind, how you will panel around the boxing, measuring, fitting and sealing. Most problems will occur if you forget to check what is behind.

What is Behind?

Wall hung pans sit securely on a framework, often referred to as a carcass or hidden cistern frame. This will be fixed to the floor and braced to the wall to help take the weight of the pan and person sitting on it. Inside this, we will find the cistern, flush piping and waste connection. A board will then be fixed to the front of the framework creating an even surface.

When panelling you need to consider two things.

The boxing will stick out from the wall. With the framework and board fitted the surface will often be between 100mm and 150mm ahead of the wall, depending on the framework and model.

The flush plate needs to be easy to access. The cistern can be accessed through the flush plate hole, you will need to cut a clean hole in your panel.

Different manufacturers (Geberit, Grohe etc.) will have different measurements for depth of the framework and size of the flush plate. Always refer to you fitting instructions for your specific model.

Check the Structure

Panelling follows the surface you are fitting to. If the surface is curved or flexing it will show through the finish within weeks. Additionally if your framing is moving the sealant around the edges of your panel will crack.

Press firmly on the front of the boxing. If it moves make sure the framework is securely fixed to the floor and wall. You will also want to lay a straight edge across the board in a few areas. If you are using adhesive to attach your panels you need a solid, dry surface. Any dents or bumps can easily be fixed now.

Most bathrooms will have a moisture resistant plasterboard covering the front of the carcass. Some fitters prefer to use a cement backer board instead as it can handle splashing and cleaning better. Choose wisely based on how wet the area is and what the manufacturer recommends.

If you haven’t already decided on your panels, look at the range here: Floors To Walls Shower Panel. The thickness and fixing type is listed on each product. This is a useful reference to see what you may need.

How you Panel Around the Box

There are 3 logical options for fitting your panels.

Wrap around the box and wall. This will give a clean finish in a small room. However you will need to cut accurately around the corners or use trims.

Panel the box. This will give you a clean finish and any small mistakes can be hidden. You can also use matching trims to give an intentional look.

Panel the wall. If your boxing isn’t too deep you could paint or tile the boxing. This will save you cutting and materials but you will need a clean edge where they meet.

Often in a narrow cloakroom the first option looks best. In a larger bathroom with a deep box the second option will give a better finish.

Plan your Layout

Before using any adhesive, place your panels in position and mark where the flush plate hole will go. Mark where the panel will need to wrap around the edge of the box.

Avoid placing a vertical joint in the middle of the hole. This is the weakest point of the panel and most likely to crack or let water in. Simply move your layout slightly so the joint is either side of the plate. This will cost you nothing.

Panels are commonly sold in 2400mm heights and 1000mm widths. Rarely will you need a full height panel for the toilet area. Often you will have plenty of offcuts from elsewhere to cover the box. When ordering allow a bit of extra as you won’t be able to fix any mistakes around the plate hole.

Before fixing, check the plate fits. The plate will generally overlap the hole however the amount of overlap will depend on the model. You want to ensure it covers the edge.

Cutting the Flush Plate Hole

• Whilst it looks intimidating, it is very simple to cut.
• Cut a piece of stiff card to the size of the hole in the board.
• Hold the card against the panel in exactly the position it would be finished in. Trace around the back.
• If you need to add a bit of extra space, as advised in your instructions, add a few mm.
• Drill a hole in each corner of the hole. Just big enough for your jigsaw blade.
• Use a fine tooth blade to cut around the hole. Ensure your panel is held securely. If your blade cuts on the upstroke keep the decorative side facing down to avoid chipping.

Round off the inside corners slightly. Sharp corners will put pressure on the panel and cause cracks.

Before fixing, place the hole against the hole and file/sand if needed. A clean edge will help the sealant to stick.

Fitting your Panels

Always follow the instructions that come with your panels. Different products will require different coverage, open times and curing times. If you are using adhesive, apply the adhesive to the board following the recommended pattern. Push the panel into place from one side and secure with masking tape. Wipe off any excess adhesive immediately especially around the hole as it will be difficult to remove once set.

If your panel is wrapping around the outside corner use trims. This will be more forgiving than mitre joints or butt joints. It will also hide any small mistakes when cutting and prevent damage to the edge.

Ensure you have left expansion gaps as recommended by your manufacturer. These are usually hidden behind trims or sealant. However panels that are tightly fitted to the surrounding areas will often curl when the room heats up and cools down.

Accessing the Flush Plate

The plate should be left unglued to the panel. Don’t seal it too much so it can’t be removed. If possible, apply a thin line of flexible sealant around the visible edge. This will stop splashing but won’t glue the plate in place.

Before finishing the room, take the plate off and reattach it. This will ensure the hole is generous, the fittings can still reach the framework and won’t catch on the edge.

Sealing the Edges

Whilst it isn’t as wet as a shower, it can still get pretty dirty. You will want to seal around the edges where your panel meets the floor, any piping going through and trim joins.

A neutral cure sanitary silicone will work with most panel systems. Apply to clean, dry surfaces. Smooth with a tool and allow to fully cure as stated on the cartridge. Don’t rush this or you will rarely get a good set. If you had to remove the pan whilst doing this, fit it back in following the toilet makers instructions. Check all connections for leaks.

Common Mistakes

• Some common mistakes include:
• Not checking if the carcass can move before fixing the panels.
• Cutting the hole freehand resulting in an uneven or large hole.
• Having a vertical joint right in the centre of the hole.
• Sealing the plate so it can’t be accessed.

Forgetting to leave expansion gaps causing the panels to curl in warm weather.

Overall planning the room will help. Using some of the ideas from our Bathroom Renovation Ideas guide will help you decide where to place your toilet and how you will finish the surrounding walls. Guide here: https://blog.crecso.com/affordable-bathroom-renovation-ideas/

Ordering and Advice

When contacting your supplier give them the width of the wall, height and depth of the boxing and position and size of the flush plate. Ask if the panels you have chosen will work with the board. Companies like Floors To Walls can usually advise on what trims and sizes you will need. If you explain how the layout looks they can give you advice. Get a sample so you can try cutting and applying some sealant to an actual offcut.

Top Tip

Always start with the structure. Ensure the carcass is secure, the board will work in a bathroom and the surface is even. Decide how you will panel around the box. Use a card template for the plate hole. Dry fit. Leave the plate accessible, expansion gaps and allow the silicone to fully cure. A clean hole and accessible cistern will make your wall hung toilet look great and last.