Polished Concrete in Wet Areas

There is common misconception of recent, regarding concrete polishing concrete in bathrooms and other wet areas (laundries, toilets, powder rooms, etc). 

Internal wet areas must be waterproofed to stop water transferring through the concrete slab and the wall floor junction.

Bathroom and wet area floors are able to have polished concrete installed, however the correct procedures need to be followed to avoid having the headache of trying to rectify quite a tricky problem at completion of your project. Firstly, consultation will be needed with both your designer/architect and the structural engineer, some previous methods for achieving compliance has been to provide a 100mm set down in the concrete slab, to allow for a 100mm concrete topping slab to be laid (topping slab is the one which gets polished).

Once the concrete slab is poured and cured, a suitable waterproofing membrane applied prior to commencing with the second 100mm concrete topping slab which is poured over the top then allowed to cure. Once cured the concrete polishing can then begin.

This will need to be documented as part of the building permit documentation, as an Alternative Solution would need to be prepared as part of the building permit approval given there is no prescriptive requirements for waterproofing polished concrete floors.

Another potential means of achieving compliance would be via the use of a suitable waterproofing product, however this is subject to the building surveyors assessment of the product specifications and testing to determine whether the desired product can be implemented as part of an Alternative Solution.

Slip resistance should also be considered and necessary precautions taken, always consult your designer or architect for slip resistance guidance when installing hard floor finishes.