kilty55

hi guys,im starting to gather info on doing a full wetroom for my parents in the near future, the room is on 1st floor with chipboard floor and plasterboard walls,,if im using wediboards do i fit the wedi tray and boards directly on to the chipboard and tape and seal the joints?? also would the joints need tanked for extra water resistance? walls i was thinking of putting water resistant plasterboard up and then tanking them also,is this sufficient to make a wetrooom or should i use a thinner wedi board on top of water resistant plasterboard for the walls using tape and tanking to finish?? any help would be greatly appreciated as usual

jgrant

Hi
I cannot comment about Wedi but use Marmox which is very similar, albeit a bit cheaper. For Marmox I would stick directly to the chipboard using a general cement based adhesive and mosaic trowel. Butt boards together using silicone sealant and then screw the boards using 25mm stainless steel screws and Supa Pro TBB washers (for 10 or 12.5mm thickness boards). Finally tape the boards with Marmox reinforcing scrim with a thin cost of cement based adhesive. At the junction of boards and tray use MArmox waterproofing tape, and between floor and wall apply a skirting using the waterproofing tape.
The MArmox showerlay tray can be laid directly to the chipboard, although this will raise the floor height by 22-28mm (depending on the tray). Alternatively remove the chipboard, deck the surface between the joists (to support the base of the shower tray) and create a box for where the drain will go. Bed the drain into a semi dry sand and cement mix (or expanding polyurethane foam) and stick the tray down with a cement based adhesive. If the levels are out with the surrounding Marmox spacer the tray off with a sheet of Marmox or a thicker bed of adhesive. Don't forget to apply waterproof tape to it's perimeter and to the wall.
I would avoid plaster board for the shower area (although this would be OK for the rest of the room. Use MArmox tile backer boards instead, with silicone sealant between the joints and re-inforcing scrim. Good luck