Civil Engineering Reference
In-Depth Information
When installing ceramic tiles it will be necessary to supply a more rigid surface on
which to apply the tiles. This can best be done by building a timber framed wall as is done
in conventional building (see Chapter 6, on timber framed walls). This timber framed
wall would then be covered with Villaboard or something similar. Personally I prefer to
line wet area walls with Villaboard rather than plaster, as I believe that this provides a
better base with a longer life expectancy. Villaboard is a sheeting product that resembles
cement sheet in appearance. It can be cut with a scorer or a cement sheet cutter. It has a
recessed edge to allow joining tape and compound to be applied to the joint without
bulging out the joint, which would be a problem when tiles are applied.
It is inappropriate to glue tiles or fix any material directly to the straw bale wall for
showers or baths as a barrier for the water must be provided.
Installation of a preformed shower base
Preformed shower bases might be manufactured from fibreglass, plastic, metal or
polymarble. The polymarble bases seem to be the most popular as they are strong with a
good surface for cleaning. A precast shower base will have a lip on the upper edge of the
shower base. The wall sheeting is to pass over this lip onto the shelf below it, thus
preventing water from flowing off the sheeting over the edge of the shower base.
Consequently the shower base must be installed so that the inside edge of the lip on
the shower base is level with the outside face of the timber framing to permit the sheeting
to drop uninhibited down onto the shelf below the lip.
When using mini-orb to line the shower, the mini-orb should be fitted to the shower
recess prior to lining the other side of the walls. Once the mini-orb is fitted, silicone seal
the sheeting to the shower base by applying silicone to the back of the sheeting down into
the shower base. Alternatively, silicone can be applied to the junction of the iron to the
shower base on the face of the sheeting, however this is much more likely to attract grime
in the future. If someone stands or sits on the outlet for the shower and the water rises to
above the edge of the shower base, and the sealant is not in place, the water will flow over
the back edge of the shower base and onto the floor. This will damage floor coverings in
the adjoining areas, and will eventually cause the timber framing to rot and need
replacing.
Fixing metal flashing around a shower enclosure
If the shower is in a corner you must fix a metal flashing in the corner at the junction of
the two walls down into the shower base over the lip of the base prior to installing the
sheeting. The sheeting must then be sealed to this flashing and to the shower base where
the sheeting meets the shelf below the lip of the base. Fit the sheeting with a 3-4 mm gap
between the surface of the shower base and the bottom of the wall sheeting. This will
enable you to seal the sheeting to the base by using silicone in the gap, preventing water
flow over the lip of the shower base. The tiles will cover not only the gap between the
sheeting and the base, but also the silicone sealant.
