a small amount of water is bubbling around the back of the base of the toilet when flushed. What type of 'washer' seals the system to the downpipe underneath and coming out of the floor? The leak is not coming from any of the water inputs.

Barry Dyke, September 2010

I don't know about roca toilets in particular, but typically it would just be a wax seal. Shut off your water supply valve to the toilet, flush it to drain the tank, and loosen the nuts on the sides of your toilet. Remove the toilet and put a new wax seal with a poly-ethalyne sleeve on the toilet, lower it into place, and reconnect the bolts.

Ryan, October 2010