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How to Waterproof a Wetroom Guide

Tanking is one of the most important parts of installing a wetroom, no matter how good the tiling and grouting is, movement and thermal expansion can cause the finest of cracks that lets water track through to your floor or walls. For this reason the British Standards Institute code of practise BS 5385-1 clause 6.1.1.3 recommends that all substrates should be tanked before tiling, "in wet areas.... substrates should be protected with a suitable proprietary tanking membrane system". 

How To Waterproof A Wetroom Guide Tanking Area

No matter which of our tanking systems you decide to install the aim is the same, to create one continuous tanking sheet membrane in the entire wet area down to the drain. At minimum tanking must be applied 1000mm up the walls and 1000mm into the room from the edge of the wet tray. 
You may tank beyond this, or even tank the entire room, this will depend on water flow or the potential splashing of water beyond the determined wet area.

These guides assume that all previous works have been carried out appropriately, the substrate has been prepared correctly, the tray is laid flat, is level with the rest of the floor and has no movement. 

Innovations Wetroom System Logo

Tanking Guide

Innovations Wetroom Tanking System Kit

The Innovations Wetroom System is an easy to use paint on tanking compound that once applied will dry into a flexible rubber sheet membrane. 

How To Tank A Wetroom Guide

Ensure the substrate is sound, free of any contaminants and remove any loose material.
Check there are no significant irregularities, any gaps should be filled using a cement based tile adhesive.

Please note - When applying the tanking compound, thicker is not better!
All that is needed is a nice even coat, painting the compound on too thick will only impede drying times and does not offer any increased performance. 

Prime the substrate, this includes all porous and non porous surfaces in the wet area and allow to dry.
The primer can be thinned as directed on the bottle.

Apply the first coat of tanking in one direction, start high in the corner of the wall, bed the tanking tape into the painted compound in the corner join as you go. Once you reach the floor bed the internal tanking corner into it using the same method.
If there are pipes coming through the wall in the wet area, use the pipe collars in the same way.
The floor is tanked using the same method as the walls.

Work your way out of the wet area making sure to continue reinforcing any joints, corners or pipes as you go.   
Allow to dry overnight or it may be brushed over after
3 hours.

Once the area has dried apply a second coat of the tanking compound, apply this in a 90° angle to the first coat. 
Allow to dry for
24 hours before tiling.

Hydromat Wetroom Tanking System Logo

Tanking Guide

Hydromat 10m Wetroom Tanking System Kit

The Hydromat Wetroom System is a Butyl self adhesive sheet membrane that may be tiled over straight away

Please note - The Hydromat system components are extremely high tack, care should be taken when handling to ensure no contact is made between them prior to being laid in the correct position. 
Joint tapes and corners are self adhesive on both sides with a removable film, when laying remove the film on the side to be stuck, place in situ and then roll over for maximum adhesion before removing the top film.
The Hydromat sheet membrane once laid must also be rolled over its entire area.

Ensure the substrate is sound, free of any contaminants and remove any loose material.
Check there are no significant irregularities, any gaps should be filled using a cement based tile adhesive.

Prime the substrate, this includes all porous and non porous surfaces in the wet area and allow to dry.
The primer can be thinned as directed on the bottle.

Install the internal/external corners.
Install joint tape into the corner wall/wall join, overlap the tape onto the internal corner on the floor.
Install joint tape into the corner floor/wall join, overlap onto the internal corner by
50mm. Do not overlap onto the vertical tape in the corner.
From the corner of the wall, mark out and apply joint tape at
1000mm centres, overlap the wall tape onto the floor tape, down to the floor.
Joint tape is not required at the edge of the wet area where the sheet membrane will end.

Hydromant Wetroom Tanking Guide
Hydromant Wetroom Tanking Guide

Starting in the corner apply the membrane onto the wall, where the membrane butt joints overlap onto the tape by at least 70mm and ensure there are no gaps greater than 5mm anywhere.

Hydromant Wetroom Tanking Guide

Mark out on the floor and apply joint tape at 1000mm centres, overlap it onto the floor/wall tape.

Before the the membrane can be fitted to the floor the interface between the membrane and the floor drain must be considered.
Please read the "Common drain & membrane interfaces" section now and apply it during the next part of the installation. 

Starting in the corner apply the membrane onto the floor, where the membrane butt joints overlap onto the tape by at least 70mm and ensure there are no gaps greater than 5mm anywhere.
Apply the Butyl Sealant to all gaps/joints. This sealant does not cure solid, it will remain permanently plastic.
You are now ready to tile.  

Hydromant Wetroom Tanking Guide
Hydromant Wetroom Tanking Guide

Common Drain & Membrane Interfaces

The Purus Minimax 2-part drain drain features a clamping ring, remove the clamping ring, mark the centre of the drain when laying the membrane and cut a 107mm diameter hole in it.
Press the membrane into the drain then install the clamping ring to secure it.
For other drains with clamping mechanisms please refer to your drain instructions.

Hydromat Membrane Installation into Purus Minimax Drain Clamping Ring

For drains that have upstands, cut the membrane to fit it around the upstand, ensure to leave a gap no greater than 5mm and apply Butyl Sealant. 

Drains without an upstand may also be used by taking the membrane at least
30mm onto the body of the drain and applying butyl sealant to the edge of the membrane.

Hydromat Membrane Installation Up To Wetroom Grid Using Butyl Sealant
Hydromat Membrane Installation Up To Wetroom Linear Grid Using Butyl Sealant
Common Drains & Membranes Interfaces
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