Joining Bathroom Cladding Panels

Unless you are covering a tiny area you will always be a need for joining bathroom cladding panels to cover a bathroom wall.

But what factors should you take into consideration when joining bathroom wall cladding panels? And what difference do the different joint types make? We will answer the most commonly asked questions and explain how the different joints work.

joining bathroom cladding panels

Tongue And Groove Joints

Bathroom cladding is an extruded product. As it is formed a joint is moulded onto either side. One side has a tongue the other other has a groove. This enables the panels to be slotted together.

Even large shower panels have this system but there are some that don’t. These are wood based systems with either a MDF or plywood core. They have a square flush edge. To join this type of panel you need a joining strip which has the profile of a letter “H”.

Panels that use joining strips are not great aesthetically because the strips are very obtrusive. Check with your manufacturer as to whether your panels are suitable for use in showers. Believe it or not there are shower panels available that are not waterproof.

Sealing The Joints

The tongue and groove joint is shower proof but not completely waterproof. You would need to deliberately need to try and force water through a joint – in general use no water will get through. The join relies on the springiness of the plastic to form the seal. Anything powerful enough to force this seal apart would enable water to get through.

However, by running a very thin bead of silicone inside the grooved side it then makes them 100% waterproof. Only a smear is required – too much sealant will make pushing the panels home difficult and sealant can escape out onto the surface. If this happens wipe it off immediately. It is not a big problem but leaving it cure before wiping it off will its remove a great deal harder.

One important installation instruction needs repeating as it affects the waterproofing aspect of the finished job. Always install your shower tray or bath first. Do not run cladding down behind the tray or bath. See our article on bathroom cladding installation tips for more info

Bathroom Cladding Joint Types

Although bathroom cladding with a tongue and groove join all slot together the same the appearance of the join will vary depending on the design. You will see references to the joint type throughout this website so will will describe the different options available and how they vary.

The 3 joint types are:

Flush Joint
V Groove Joint
Contrast Joint

All 3 are still tongue and grooved it is just a matter of personal taste as to which you think looks the best.

flush effect panel joint

Flush Joint

This is the most common join used for bathroom cladding. There is still a tongue and grooved joint going on behind the surface but the front of each panel meets the next one “flush”. There is a slight join line but this is not really that noticeable. It is akin to wallpaper in that there is a join but it is not the first thing that you see.

Tile effect panels disguise the join to the point where it is not visible unless you look very hard. The vertical design of the tile pattern draws the eye away from the join.

This type of joint is perfect for use in showers, above bath and any wet areas. The smooth surface is easy to wipe over and does not collect dust or soap residue.

V Groove Joint

Again, this type of panel has a tongue and groove join behind the scenes but the edge of each panel is chamfered. That means when the panels come together there is a groove or V visible down the join. V Groove panels make a feature of the joint and results in a finish that resembles planks.

In the drawing you can see that there is a secondary chamfer half way along the panel effectively making one panel look like two planks. This is referred to as a 2 Plank Effect Panel. There are 3 plank effect panels on the market but these are less common.

The most frequent use for this type of joint is with ceiling panels. The join is still totally waterproof so they are suitable for use in showers. But the chamfered edges make them harder to clean as the soap residue can build up in the groove. Obviously this is not an issue if used on ceilings.

joint contrast

Contrast Joint

This is another joining system that makes a feature of the joint. This time a strip runs down the panel vertically. This is either a different colour to the main panel or a metallic finish strip.

The strip is either moulded into the panel (most common) or it comes as a separate item that clips in place around the edge. Grosfillex had a range of panels called Ambiance that employed a coloured, moulded-in contrast strip. But these are no longer available.

Chrome infill strips are a popular addition to ceiling panels . They are not suitable for use in showers or above baths as they do not form waterproof joints.

Square Edge Panels

There are panels available that have a square edge. There is no tongue and groove joint. This type of panel is usually larger in size and can be made from any number of materials. But it would not usually be classed as bathroom cladding, instead it would normally be some form of shower panel.

The materials used for this type of panel can be laminate, PVC or Acrylic. These panels have to be joined together using a joining trim because there is no tongue and groove. The joining trim is an H section into which the panels slot. They need to be sealed into the trim with silicone sealant to make a waterproof joint.