How to install a back-to-wall corner bathtub? The guide

Do you dream of the contemporary design of a freestanding model but face architectural layout constraints? Installing a high-end bathtub in the centre of the room requires a large amount of space. This is where the hybrid configuration truly makes sense to transform your bathroom.

Halfway between a freestanding bathtub and a classic built-in installation, choosing a back-to-wall bathtub stands out as the ideal alternative. This type of equipment combines the refined aesthetics of curved sides with the practicality of an installation against a wall.

By choosing a corner bathtub, you make the most of unused corners while bringing a resolutely modern and geometric character to your space. It is the technical secret to achieving maximum space saving without compromising on the comfort of a large relaxing bath.

Thanks to its factory-integrated acrylic apron, this model eliminates the tedious step of building an apron with plasterboard or aerated concrete panels to be tiled. Choosing and installing this solution allows you to save valuable time on your renovation project.

Whether you have a spacious bathroom or a small bathroom, installing this structure is accessible to any meticulous DIY enthusiast who masters PVC bonding and the basic rules of plumbing.

The materials and tools needed for installation

To successfully complete the installation of a corner bathtub without making a technical mistake, preparing the tools in advance is essential. Unlike built-in models, you will not need any masonry materials, but rather precise measuring and tightening instruments.

Here is the complete list of materials to prepare on the floor before starting:

• A spirit level of considerable length (minimum 60 cm) to adjust the flatness on both axes.
• A drill-driver fitted with drill bits suited to the nature of your wall (tiles, plasterboard, brick).
• A cartridge of fungicidal sanitary silicone sealant (anti-mould treated, in translucent or glossy white finish).
• A tube of glue for rigid PVC and fine sandpaper.
• A flexible waste connection including a corrugated PVC flexible hose with a diameter of 40 mm.
• A complete technical waste kit including the bottom drain, the overflow and an extra-flat trap.
• A set of open-end spanners or an adjustable wrench for precise adjustment of the height of each foot.
• A builder’s pencil and a tape measure.

Our range of back-to-wall bathtubs

Step 1: preparing the floor and connecting the plumbing

The first technical phase consists of preparing the water supply and drainage waiting points. The hot and cold water inlets should ideally be positioned on one of the two wall sections forming the corner, depending on the type of tapware selected:

• If you choose wall-mounted tapware, make sure to respect a standard centre distance of 150 mm between the two offset connectors, at a height generally between 70 and 80 cm from the finished floor.
• If you install a mixer directly on the rim of the bathtub, the braided stainless-steel hoses will connect in the lower section under the edge, hidden from view.

The drainage system is the critical point of the installation:

1. Locate the 40 mm diameter PVC waiting pipe coming out of the floor or the lower part of the partition. You must imperatively guarantee a minimum drainage slope of 2 cm per linear metre towards the main stack to prevent any risk of water stagnation or blockage.
2. Dry assemble the extra-flat trap under the tub by installing the supplied conical sealing gaskets.
3. Measure the distance needed to reach the wall outlet and cut the PVC pipe or configure the corrugated flexible hose.
4. Clean the ends with solvent cleaner, apply cold PVC glue, then fit the connection pieces together permanently. Avoid overly abrupt 90° elbows to make the flow of water smoother.

Step 2: adjusting the feet and positioning the acrylic bathtub

Once the plumbing has been prepared, move on to the mechanical assembly of the structure. An acrylic bathtub is very lightweight, which makes it much easier for one person to handle, but it requires perfect stability once filled with water.

Follow the positioning procedure step by step:

1. Carefully turn the bathtub over onto cardboard or a thick cloth to protect the acrylic surface from scratches.
2. Firmly screw the threaded rods of the metal feet into the threaded inserts integrated into the reinforced frame on the underside of the tub.
3. Put the structure back on its feet and position it dry at its final location, perfectly pressed against the two wall sections forming the corner.
4. Place your spirit level on the upper rim of the tub. Adjust the height of each adjustable foot one by one by tightening or loosening the locking nut until you obtain perfect horizontality both lengthwise and widthwise.
5. When the level is impeccable, lock the counter-nuts with an open-end spanner to secure the adjustment. All the feet must be in perfect contact with the floor to distribute the load evenly and avoid any creaking or bending of the material during use.

Check your installation dimensions

Before finalising your bonding work, consult our detailed installation plans.

Step 3: tapware and peripheral silicone sealing

The third phase seals the integration of the bathtub into its masonry environment. The treatment of the junction between the upper acrylic apron and the tiled wall determines the durability of your installation against water infiltration.

Whatever finish you choose, the peripheral sealing must be carried out with the greatest care:

1. Clean and degrease the contact area between the upper lip of the bathtub and the tiled wall with household alcohol.
2. Fill the bathtub completely with water before applying the sealant. The weight of the water will force the structure into its lowest possible position.
3. Then apply a regular and continuous bead of high-quality sanitary silicone along the two walls forming the corner.
4. Smooth the joint in one single motion using a sealant smoother or your finger dipped in soapy water.
5. Leave the bathtub full for 24 hours until the silicone has fully dried: this will prevent the joint from moving and tearing during your next baths.

Conclusion and maintenance: the commitment of a major French brand

Taking care of your wellness space is child’s play thanks to the intrinsic properties of modern materials.

The premium acrylic selected for the manufacture of our corner models has a completely smooth, non-porous and highly hygienic surface. Dirt and limescale do not cling to it, which preserves the shine of its glossy white finish year after year.

A simple soft sponge soaked in a mixture of warm water and neutral liquid soap or diluted white vinegar is enough to restore the tub’s full shine. Rinse with clean water after each use and wipe with a dry microfibre cloth to remove water droplet marks.

By following these few simple rules for installation and maintenance, you will peacefully enjoy your haven of calm, backed by a guarantee of absolute technical reliability.

Discover our range of back-to-wall bathtubs

Additional information on installing back-to-wall corner bathtubs

Can a back-to-wall corner bathtub be installed on a wooden floor?

Yes, this is entirely possible because an empty acrylic structure is very light (around 35 to 45 kg). Since a solid base is required, however, you should check the load-bearing capacity of your joist structure to support the combined weight of the water (150 to 200 litres) and the user in order to avoid any bending of the structure.

How can you create an access hatch on a back-to-wall model with an integrated apron?

These high-end models have a factory-sealed apron for reasons of rigidity and aesthetics. The technical trick consists of not sealing the product to the floor but connecting it via a high-quality extra-long PVC flexible hose, allowing you to lift the bathtub slightly by a few centimetres in the event of heavy maintenance without disconnecting the plumbing.

What length of PVC flexible hose should be chosen for easy connection?

It is strongly recommended to use a corrugated flexible pipe with a minimum length of 100 to 120 cm. This length provides enough movement to apply the bead of glue, connect the drain when the bathtub is tilted onto its side, then lower it vertically onto its feet without pinching the drainage pipe.

Should the bathtub feet be fixed directly into the floor?

It is not necessary to drill into your floor tiles to anchor the feet. The weight of the water naturally stabilises the structure. To eliminate any micro-movement, simply apply a small amount of polyurethane sealant or high-density silicone under the plastic base of each foot during final positioning.

What type of mixer is recommended for installation against a wall?

The ideal choice is a wall-mounted thermostatic mixer equipped with an anti-scald safety system. It pairs beautifully with the geometric lines of the back-to-wall format. Make sure to order column adapters if you need to adapt the centre distance of your old pipework without redoing the wall chases.

How can you compensate for a wall corner that is not perfectly 90°?

If your partitions are not perfectly square, empty gaps will appear when the tub is placed against them. You can correct a minor out-of-square issue (up to 8 mm) when tiling the wall by applying more tile adhesive to the back of the tiles, or by filling the gap with a white PVC sealing profile before applying the silicone joint.

What drying time is recommended for the silicone joint before the first bath?

It is essential to allow the sanitary silicone sealant to cure for a minimum of 24 hours (ideally 48 hours for thick corner beads) before any water splashes or any use of the bath. Leave the tub under load (filled with water) throughout the drying phase to guarantee the optimal elasticity of the peripheral bond.