Wet rooms give the impression of greater space along with a feeling of luxury. They are easier to keep clean and a fantastic way to open up space, making it especially great for those with limited mobility. Furthermore, wet room systems are not limited in sizing, like shower trays often are, so they are also a great solution for awkward or tight spaces such as loft bathrooms or alcoves.
Whether you are considering the jump to wet rooms or just looking for inspiration, wedi – the leading manufacturer of wet room solutions since 1983 – offers valuable insights on perfectly executed wet room installations.
Wet rooms are a big project to take on and it is extremely important to be aware of the British Standard (BS) requirements and of the limitations of popular materials. According to BS 5385 Part 1 “materials that are subject to movement from changes in moisture content should be avoided”. Therefore, timber sub-floors, plywood and other wood-based sheets or boards are not suitable for tiling in wet, frequently damp, or high humidity areas.
The principle of wet room design is that the entire space is ‘tanked’ or waterproofed before tiling.
Substrates should always be protected with proper tanking such as with waterproof sheet membrane, applying a paint-on liquid wall membrane or with a completely watertight tile backer board.
“Traditional tanking of a wet room is a multi-step process which entails several layers of waterproofing to ensure an excellent seal. Commonly used tilebacker boards such as cement boards, gypsum boards, magnesium oxide and expanded polystyrene (EPS) boards require additional waterproofing. On the contrary, wedi tile backer boards made of extruded polystyrene (XPS), are 100% waterproof and hence no additional tanking is required. What’s more, they are also coated on both sides with a glass fibre mesh reinforced cement coating to allow for direct tiling and so, priming wouldn’t be required either. Additionally, our boards can also be directly bonded to stud frames, so there is no need for mechanical fixing that would entail laborious sealing steps over the penetrations. Our industry famous versatile wedi 610 adhesive sealant takes care of not only the waterproof adhesion to frames, but also of the bonding and sealing of wedi building board joints in just a single step. Through reducing installation steps, our product solutions eliminate the risk of failure” – says Ciaran Feeney, Technical Manager at wedi UK.
Always make sure that your chosen tiles have an appropriate non-slip rating and low heat-conductivity.
The chosen tile backer board must also be capable of carrying the load of tiles as well as the tile adhesive. Beware of some commonly used materials such as gypsum plasterboards that have vertical weight-load capability of only 32 kg/m² limiting the choice of tiles significantly. Ceramic tiles are not ideal for wet rooms because their construction and high-shine finish makes them cold to the touch. This can result in much surface condensation making them slippery.
“wedi building boards have 133 kg/m² vertical weight-load capability, allowing for heavier, large-format porcelain or natural stone tiles to be used in the wet room. It is an understatement that grout lines provide perfect breeding ground for mould and bacteria. Thanks to the reduction of grout lines, large format tiles are an excellent choice not only for hygiene but also for ease of maintenance” – explains Mr Feeney.
Tile the space from floor to ceiling whilst ensuring proper drainage and adequate sealing of the drain.
The room needs to be tiled throughout with a gentle gradient in the main shower area. If you have a wooden sub-floor, the way your joists run is crucial to where your drain can be positioned.
“Apart from tilebacker boards, we also offer directly tileable 100% waterproof XPS flush-to-floor shower elements in a multitude of formats and sizes. Each Fundo shower element is precision engineered in Germany and features integrated gradients as well as an enhanced cementitious coating to account for the high water exposure in shower areas. They can also be easily trimmed on site to ensure an exact fit. For a universal, flexible seal around the perimeter, we offer a sealing set consisting of a special waterproof slurry, sealing tape and preformed sealing corners” – says Ciaran Feeney, Technical Manager at wedi UK.
A typical electric shower has flow rates in the region of 4-8 litres per minute, whereas a power shower could be up to 20-30 litres per minute. Flow rates of additional hand-held units and body jets should also be taken into account. The sealing of the drainage is a crucial step of every shower installation, but the stability of the drain body is also paramount.
“wedi Fundo shower elements offer a flow rate of 30-66 litres per minute depending on the design. They are fitted with a partially integrated, 360° rotatable dry-fit drainage technology meaning that no additional sealing or silicone is required for the installation of the drain. What’s more, we also offer drain substructure elements for accurate support and alignment of the drainage, especially for installations in timber floors” – continues Mr Feeney.
Whether with point or linear drainage, there is a Fundo shower element for almost every requirement. The surrounding floor should be lined with either wedi building boards or with a wedi Subliner membrane to ensure the proper tanking of splash areas.
Consider under-tile heating to keep the space warm and dry.
Tiled surfaces can get quite cold and hence it is important to take extra steps. Beneath all UTH systems, whether it be an electric or a hot-water system, there should be an insulated board to enhance the efficiency of heating.
“Thanks to the excellent thermal properties of wedi XPS elements, heat is reflected back into the room. This will not only reduce surface condensation within the wet room, but it is precisely this characteristic that makes wedi building boards and Fundo shower elements perfect to use beneath underfloor heating: they improve the response time of heating systems by up to a staggering 70%” – explains Mr Feeney. Adequate mechanical ventilation must also be installed in line with building regulations.
Concerned about splash areas?
The gradient or slope can be extended further out of the shower area with the aid of sloping boards to guide the water back towards the drain.
A true wet room is completely open without any glass partition. However, a simple fixed glass panel creating a walk-in shower area is a practical choice and has become a popular trend.
In cases where a step-up into to the wet area is required, the step should be at least 10cm high, as anything lower can be easily overlooked by those not familiar with the room and become a trip hazard.
“Architects, contractors, as well as end-users know the importance of waterproofing. Everyone knows someone that has had a leakage problem. The key thing is to know how to effectively prevent such issues with the right material. There has been a flood of tilebacker boards in the industry over the past decade, but it is important to know that not all are made from waterproof material or that the quality may be lacking. Do it once, do it right – research. A wet room is an investment, there is no doubt. However, with using the right type of material, thanks to the added waterproofing a wet room will not only add value to the property but also future-proof your home for years to come” – advises Ciaran Feeney, Technical Manager at wedi UK.