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This faq is currently being updated, please also take a look at the new guides.

1. Is there room for a wetroom and where can I fit it?
2. I've heard that wetrooms only work in larger spaces?
3. Will my wet floor be true-level access (no step)?
4. What size of underlay do I need?
5. What tiling options do I have with a centre drain?
6. I prefer vinyl to tiling. How should I proceed?
7. Can I really fit it myself and how is it fitted?
8. Will it leak?
9. Should I tank/waterproof the whole room?
10. Do I need a horizontal or vertical drain?
11. I've learnt that some underlays (floor formers) have a 'bowl' depression that is difficult to tile. Are yours like that?
12. I prefer the look of a channel drain, can you supply underlay for them?
13. Where would a pump be used?
14. My bathroom is in a block of flats/ basement/ loft/ attic. There is no way to drain the shower water away and no room even for the standard 83mm drain. How should I proceed?
15. Do I need a screen or a door?
16. Can I have UFH in a wetroom?
17. How do I find a specialist installer?
18. What is the cost?
19. I think I need a bespoke underlay. I want a large wetfloor 1800 x 1800 but your biggest Underlay is only 1500 x 1500: How should I proceed?
20. I want to place an order - what technical information do I need?

 Is there room for a wetroom and where can I fit it? 
A space of 700 x 700 is sufficient. This could be an existing cloakroom, toilet or below stairs, an attic or a basement. Use our 800 x 800 Underlay wet-floor former and reduce to size. Replacing a bath is another option using a 1300 x 800 or 1500 x 800 Underlay. For a new location a lack of water supply is no hindrance as a supply pipe can be taken anywhere. The main obstacle is drainage. The waste pipe (50mm or 38mm) must run to an external wall or soil stack. Our drain is only 83mm deep so requires minimal space below the floor. This will achieve a level-access wet floor flush with floorboards. However, the final drain height & position may dictate a raised wet floor on a 18mm plywood box, which can still be tiled for a wet room look.

The offset drain holes in our Underlays allow for optimum drain location between joists. Reducing the size ( trimming one edge ) also allows more fine adjustment.

 I've heard that wetrooms only work in larger spaces? 
This is a myth spread by plumbers who prefer to install what they are familiar with ie cubicles. Wetrooms work best in small British bathrooms as the space is not cluttered with bulky cubicles or baths (optional). By opting for wall hung basin (without a pedestal) or WC you will be amazed how the space is visually enhanced: the full floor area will be visible and liberated.

 Will my wet floor be true-level access (no step)? 
Our Underlay base is only 20mm or 24mm thick to level-off with floor boards so there is no step. However the drain body is 83mm deep (see below) and if this cannot be accommodated below the floor to give a fall on the waste pipe, a raised wetfloor is required. The result will still be a proper wetroom.

 What size of Underlay (Floor Former) do I need? 
There are two factors to consider. On timber floors assess the available space in the room and decide on the showering space required. Then consider joist direction and spacing. The drain is 83mmm deep and needs a pipe connection to a soil stack or outside wall. Some Underlays have an offset drain hole to permit convenient location. Choose the Underlay with the right balance of drain hole position and overall size to suit your space.

Concrete floors have no joists so there is a wider choice of Underlay size, space permitting.

 What tiling options do I have with a centre drain? 
There are two options with a centre drain. Tiles can be cut diagonally into the depression angle of the underlay or cut against the walls. Tiles must be laid or cut to follow the depression angles of the Underlay. Always use a bag-powder flexible tile adhesive for wall and floor tiling (not ready-mixed type). Cutting of tiles can be avoided by using a mosaic of 40 x 40mm or smaller (min. 25 x 25mm).

A centre drain underlay is shown but the same principle applies for an offset drain


 I prefer vinyl to tiling. How should I proceed? 
We have Maxxus in 9 sizes & 22mm thick. It is a structural GRP product and will span joists without underboarding. Is is pictured on the Product page. It comes with a drain and clamp ring to seal around the drain, no tanking will be necessary but you must employ a specialist team to weld the vinyl into an upstand 100mm up the wall perimeter: This forms the membrane.
Maxxus can also be tiled with a square stainless steel tile adaptor set 155 x 155 or 175 x 175.

 Can I really fit it myself and how is it fitted? 
If you are handy and confident - Yes. If you struggle with self assembly furniture - No. Detailed instructions are available free with every kit package. The work involves joinery and plumbing so show either tradesman our instructions and they will be competent - or try a general builder. Many customers elect to do the whole job except plumbing, so use a plumber for first and second fix. We are establishing a database of fitters. Full instructions are supplied with orders and Granfix tanking has instructions on the box.

 Will it leak? 
Using the membrane and instructions correctly prohibits leaks. We offer a life of tiling or life of vinyl guarantee, provided the instructions are implemented correctly. See printed matter for full wording. For the ultra-cautious user the dual membrane solution is the answer - apply WOP first then brush on Granfix.

 Should I tank/waterproof the whole room? 
If it's a small room, say below 4 or 5 sq metres, it can be just as easy to do the whole room as it is likely to be stripped out anyway. However, the wet area only needs to be done. The wet area is defined as Underlay size x 2. This allows a generous 'overlap' for splashing, even if a screen is used.

 Do I need a horizontal or vertical drain? 
It depends where the soil stack or external drain pipe is situated. In most cases a horizontal one will run out between joists, or a trough in the concrete. If on a second or third floor it may only be necessary to run the waste pipe to the room below (vertical).

The drain is 83mm deep by 112mm diameter at the top reducing to 90mm. To allow tiling the visible grid is 143 x 143 square, made of polished stainless steel. Six designer grids are available at extra cost. The outlet neck takes a 2 inch 50mm pipe (solvent weld) but a reducer to 1.5 inch (40mm) is included. Flow is 32 litres/minute.

 I've learnt that some underlays (floor formers) have a 'bowl' depression that is difficult to tile. Are yours like that?  
No ours have four flat sides, not a concave bowl. This makes them easy to tile with large-format tiles or mosaics. The concave bowl type is designed for vinyl flooring or we have Maxxus underlay for this.

 I prefer the look of a channel drain, can you supply underlay for them?  
We offer two kinds, both to suit Purusline drains.

To position a Purus channel drain against a wall Wedge-Dek is available in 5 sizes.
It is unique in sloping in one direction only. Two Wedge-Dek can be placed back to back to cover a larger floor area.

The Centre Linear comes in 2 sizes, offering a different aesthetic with a conventional slope on four sides.

Maxxus Channel Drain Deck comes in 2 sizes, available Autumn 2009.

 Where would a pump be used? 
The chosen location may be on the opposite side of the house to the drains. It may be in a basement below the level of existing drains, or in a position that precludes a gradient to allow drainage. In a roof space headroom may be so tight that to raise the floor to take a standard drain would reduce headroom.

As the pumped drain is only 35mm deep it permits installation in areas of restricted access. The pump has a sensor to automatically start when water is present.

 My bathroom is in a block of flats/ basement/ loft/ attic. There is no way to drain the shower water away and no room even for the standard 83mm drain. How should I proceed? 
By using a flow-sensing pump, the Dry-Deck 20 pump senses water in the supply pipe and automatically starts up, sensing both hot and cold water. Pump speed is matched to shower flow rate. Afterwards any remaining water is removed by automatic re-starting after 15 minutes for a period of 20 seconds. The pumps is maintenance free, needs no filter and is hidden in the wall behind an access panel. It is almost silent running.

The gulley for tiling is only 35mm deep and for an acrylic tray is 50mm deep. There is also a gully for vinyl floor covering. The flow rate is 20 litres/min.

The underlay floor formers are only 20-24mm thick, to be level with floorboards or set into concrete.
This means in the most difficult locations you can have a wet room without a step, a tray or even a door. See picture at bottom of products page.

2 year warranty and national service network.

 Do I need a screen or a door? 
Practicality in a small space is important so use a screen to prevent splashing of sanitary ware eg. basin or wc, or for privacy (satinised option). We stock minimal splash screens from only 200mm wide.

 Can I have UFH in a wetroom? 
Yes, even directly below the shower head except for a few electric systems.
Click onto UFH for fitting instructions and pricing.

 How do I find a specialist installer? 
Try Yellow Pages or, although we are establishing a list of specialists, so phone the office. If you are an installer wishing to be added to the list, please write in.

Wet Rooms are available at Heat and Plumb

 What is the cost? 
We supply trade, retail and wholesale. Click on Price List. Kits are available £730 - £929 including screen. A key benefit of our system is that only the 'wet' area needs waterproofing, reducing costs to a third of usual levels.

 I think I need a bespoke underlay. I want a large wetfloor 1800 x 1800 but your biggest Underlay is only 1500 x 1500: How should I proceed? 
The Underlay is merely the floor former so use it as a basis for the centrepiece of the floor. The edge thickness is 24mm so simply extend each edge of the Underlay using 24mm plywood (4 strips 1800 x 150mm with mitred ends). To continue the floor slope use packers on the outer perimeter edge. Apply your chosen membrane in the usual way.

Alternatively we have extension pieces 300 x 1000mm that extend the gradient on any edge you choose

Finally Megadek offers a single gradient 2500 x 1350mm with a flexible compound for timber or concrete floors.

 I want to place an order - what technical information do I need? 

General: We need to know floor construction and floor surface material.
Underlay: Underlay can be reduced in size by 150mm using sharp knife, handsaw, any electric saw or angle grinder.
Showerstone can be reduced by 80mm with an angle grinder.
Maxxus can be reduced by 150mm with an angle grinder.
Drain: We need to know if outlet is at bottom or side to align with waste pipe.
Tile backer Board (Marmox): Size - 600 x 1250. In thickness 4, 6, 10, 12.5, 20, 30, 40, 50. Marmox is similar to Wedi but cheaper than and double the reinforcement. Totally waterproof foam - cored, not just moisture resistant and lighter than Hardibacker or Aquapanel, also non-hygroscopic. Use beneath underfloor heating or as a membrane (see Marmox Board leaflet).

Marmox certification Marmox Banner
Tongue & Grooved Lining Panels: Hollow Core is featherweight hollow panel 2600 x 250 (+ tongue) x 10. Formica mdf has heavy mdf core 2420 x 1215 x 11 with square edges, one being lipped. Optional U-shaped edge trim 2500.
Membrane: 4 types also known as tanking

Method 1
Granfix: Liquid. Brush-on two coats. 2mm thick. Simple and cheap, ideal for beginners. Coverage 7 sq metres

Method 2
Marmox 600 x 1250. 10 or 20mm thick. Seal joints & edges with tape and liquid in Granfix kit as above.

Method 3 & 4
Sheet membrane. BSA or WOP. Send for leaflet.

Compatible with all kinds of UFH.
Detailed fixing instructions free with every order. Instructions MUST be followed. Failing to follow instructions invalidates any warranty.


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