THE TILE SOURCE - Solutions for wet rooms
How you waterproof the floor of your wet room will depend on the floor construction and what type of underfloor heating system you will use. You will also need to consider the finished floor level and how the shower tray, drains and floor relate to each other. Under each of the main floor types below we list our prefered waterproofing solutions. All the products listed are available from stock and at the best possible prices. Also see Wet Room wall solutions.Getting your levels right
You should have already checked that your Marmox Wet Room shower drain and showerlay tray will fit and work (see wet room solutions). Next you need to consider your finished floor height. This will be your existing floor height plus the tile (10-20mm), plus adhesive (allow 3-5mm), plus underfloor heating cable (5mm) or foil (1mm), plus Ditra matting (4mm) or Marmox (6,10,12.5 or 20mm). A large step up into the room may be unsuitable, or alternatively it may be a new build which can be designed so that the finished floor is flush with the external flooring.
The Marmox Showerlay tray will need to be set into the floor so that the top of the tray is at the same level as the surface that will be tiled. These instructions presume that the only drainage falls will be created by the shower tray. All other finished floors will be flat. Alternatively the Showerlay tray base could be higher than the rest of the floor and a raised step formed round the tray (see photo on the right).
Timber floors
Ensure the boards are firmly fixed and level. There are two solutions, the first is Schluter DITRA matting and KERDI KEBA tape The matting is used as a waterproofing membrane and uncoupling system (movement in the timber floor will not be transfered through to the tiles). The tape when fixed with Schluter KERDI-COLL adhesive is used to waterproof the joins in the matting, the join with the Marmox Showerlay tray and as an "L" shaped skirting around the floors perimeter to waterproof the joint between the floor and wall. This system's major advantage is being only 4mm thick (including the adhesive to fix it).
The second solution is to fix Marmox boards to the floor using 15 stainless steel screws and SUPA PRO TBB washers per board. The screw lengths should be a maximum of the Marmox board thickness and the thickness of the timber floor. A high quality silicone sealant (such as Dow Corning 785) should be applied to the edge of the board and the next board to be fitted should be butted up against the silicone sealant. The edges of the boards should be taped using self adhesive Marmox fibreglass scrim tape covered with a thin skim coat of adhesive. The boards are available in 10,12.5, 20 and 50mm thickness. All board sizes are 1200x600mm apart from the 12.5mm which is 2500x1200mm. The main advantage for Marmox boards is that they are excellent insulators and work well under underfloor heating systems. A 6mm board is also available, although this must be stuck down using Ardex 7001 adhesive. The perimeter of the room and any extruding pipes should be waterproofed using BAL WP1 waterproofing solution and fibregalss scrim.
Screeded floors
All the solutions are the same as for timber floors except that the Marmox boards will need to be stuck down using one of our cement based adhesives. If it is a new screed you will need to wait 4 weeks for it to dry and cure before commencing tiling.
Underfloor heating
A wet room would not be complete without an underfloor heating system. The luxury of walking on warm tiles has to be felt to be believed and it also helps to keep the floor dry. Magnum Electric Underfloor Heating have three solutions available:
1. Magnum enerCable, this can only be installed in a new screed and is not suitable for timber floors or old screeds. It will not raise the floor height and is particuarly cost effective. It will require an electrician and the placing of a thermostat on the wall and a sensor in the screed. If using Enercable you must use the Schluter DITRA matting and KERDI waterproofing system.
2. Magnum enerMat, this would be installed on top of the waterproofing and would raise the floor by 5mm. It will require an electrician and the placing of a thermostat on the wall and a sensor in the floor.
3. Magnum enerFoil, this very safe low voltage system would be installed on top of the floor waterproofing and would raise the floor by less than 1mm. No sensor or thermostat would be required, however it is run off a transformer that would need to be nearby (for example in a wardrobe) and it would require a three pin socket.