Sizing a wet room former
Aquadec EasyFit
Linear 2 Wet Room floor former
Linear 3 - Wet Room floor former
Linear 4 Wet room floor flormer
Aqua-Dec wet room floor
Aqua Grade wet room floor
Novellini DUO floor deck
Novellini Quattro floor deck
Solid floor Linear shower drain

How to size a wet room shower floor former

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Wet room floor former size guide

Guide to choosing the right wet room floor former

Index > All about wet rooms > Wet room shower floor formers > IMPEY Aquadec > How to choose the correct size Floor forer for your wet room shower

Using a wet room floor former

Finally, a solution to the age old problem of forming a wet room floor. Wet rooms have been popular on the continent for years, but inherent problems creating a suitable floor and waterproofing resulted in the UK being a little slow to catch on to the idea. Now that there are products to guarantee a perfect job every time the wet room is fast becoming the preferred installation.

Wet room shower floor former creates a perfect shape

Products such as those from Impey (Aqua Dec Easyfit, Level-dec, LinearFlo dec and Aquagrade) or Novellini (Duo Deck and Quattro Deck) present easy-to-install solutions for just about any project. Associated waterproof tanking products add that final assurance that only your wet room gets wet - not the rest of your property!

A floor former simplifies the creation of a wet room shower floor

Creating a steady gradient towards the waste outlet is not as simple as it sounds. Sure you can make a shape in a floor, but will the angle be consistent and will the structure withstand the test of time? Creating a slope in a floor manually takes quite a while, so if time is money the use of a floor former makes perfect sense. Not only will a floor former offer you a ready-made slope towards the waste (at the perfect angle), it also offers a strong and durable floor -  enhancing structurally rigidity in the showering area. Furthermore, waste traps are designed to work with their respective floor formers ensuring a watertight installation (no drips or leaks in places you cannot see or subsequently get to easily!).

Specialist wet room shower screens

To compliment your project are an outstanding selection of wet room shower screens. Impey offer frameless, clear-glass screens in the Aquascreen range, Novellini offer Italian styling in their Kuardra and Giada ranges.  Using the right type of screen gives the showering area that finishing touch.

What size wet room shower floor former should I use?

Floor former sizes

Wet room floor formers (also referred to as a floor trays) are available in a number of popular sizes. Needless to say, if your wet room area and one of the tray sizes happen to match then there is little to decide. However, not all installations will enjoy such a happy coincidence.


What if the standard floor former is too big?

There are obvious advantages in choosing a floor former that is as close to the size of shower area you wish to install. But remember, although it is unlikely you will wish to exceed the area in which you will shower by much it is not a problem if the former protrudes slightly outside the showering area. The slope on a wet room floor former is subtle, so having it extend slightly into the room should not cause issues or be aesthetically unattractive. Indeed, if you intend to utilise glass shower screens you may prefer to have the drips from the glass landing on the slope towards the gully so a bigger tray might be considered advantageous. (This may not apply if you wish your door or screen to remain in contact with the floor)


Trimming a wet room shower floor former

Floor formers can be trimmed. On each size you will see an area on the perimeter designated as the 'trimmable area'. This may be left as is or trimmed to reduce the deck size by the stated amount if it happens to be slightly too big or the wrong shape. It is not advisable to trim beyond this area as the slope of tray could be compromised.


What if the floor former is not big enough?

(The following should not be taken as official guidance and may not represent the opinion of the manufacturer)

You may find the situation arises where you are left with a reasonable gap to the wall around the tray having selected the nearest size floor former for your shower area. This is where you might need to become a little creative. There is no 'absolute' way to handle such a problem, but within reason you can overcome such an inconvenience.


Within reason you can 'extend' the showering area beyond the perimeter of the former. There can be several ways to achieve this depending on the construction of the floor and the type of floor covering being used. The other obvious factor will be how much of a shortfall you have to make up.


For example:

We will assume you are tiling the floor and your wet room floor former is approximately 200mm short of the target width within an alcove.

To begin, it might be desirable to centre the floor former within the alcove - leaving approx 100mm (4") either side to the wall.

It is recommended you waterproof your shower area with a tanking membrane.

When tiling, simply comb your floor adhesive across the deck in the normal manner spreading into the 100mm shortfall area either side of the tray.


The wet room shower floor former installs into the floor, sitting onto the joists.


Aquadec installs into the floor onto joists*.


*Manufacturer's recommendations should be followed with regard to reinforcement and/or additional support under the floor former.


Centre the wet room shower floor former within the alcove.


When tiling, bed your tile on the adhesive in the shortfall area at a slight angle similar to the angle of the tiles on the shower area - extending the run of tiles from the floor former to the alcove wall.

The extended slope is made within the adhesive around the periphery. As the fall on the floor former is only slight so will the fall be on your extended perimeter. If done well it shouldn't notice.

Centre your Aquadec leaving equal spacing either side


Many installations require a little lateral thinking. Whatever your requirement happens to throw at you a wet room floor former is an excellent place to start creating your wet room shower.

All that's left is to choose which range you wish to use.

To the main Wet Rooms page


Slightly angling the tiling beyond the wet room floor former reaching the alcove walls effectively extends your shower area.


Extend your tiling beyond the edge of the Aquadec



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Sizing a wet room shower floor former