How to insulate a bathroom

To make a bathroom warm in winter and cool in summer we can insulate the floor, wall and ceiling.

Here is an example of insulating a bathroom with a concrete base and a timber floor.

The timber pallets for the floor are also warm underfoot in winter, and cool in summer.  Timber is far less polluting a material than tiles as it takes less energy to make and install and there’s less or no waste during construction.

This post is about the insulation; the timber flooring will be explained in a later post.

The concrete base was chosen, reluctantly, as it was the best option to manage the water from the showers and washing there.

Four layers were placed under the concrete before it was poured on top and commencing from the bottom layer up they were:

  • A strong plastic layer directly onto soil to confine water to the area above it;
  • A very efficient (the most efficient we could find) layer of insulation (Polyair Performa 7.0).  This insulation is used here for all locations; the floors, walls and roofing;
  • A layer of thin corduke over the insulation;
  • A layer of plastic;
  • Then the concrete was poured over that.
The bottom plastic layer before the insulation, corduke are placed on top.

The bottom plastic layer before the insulation, corduke are placed on top.

The insulation on top of the black plastic and turned up to cover the concrete yet to be poured, with the corduke on top to increase the efficiency and protect the insulation.

The insulation on top of the black plastic and turned up to cover the concrete yet to be poured, with the corduke on top to increase the efficiency and protect the insulation.

 

All layers except the corduke were turned up at the side to the height of the planned concrete pour which would form the base on which the timber floor pallets were to be built.  The layer of insulation will be continued up the wall and across the ceiling.

The post about the timber flooring will be published in a few weeks.