Can You Put a Toilet Where a Bidet Was?

The Bidet

• Designed and used for washing the private parts, a bidet is nothing more than a sink on the ground. In those terms it is easy to imagine the connections -- hot and cold water in, and a waste-water pipe out that leads to the sewer system serving the building. While it initially appears that reusing those connections to fit a toilet would be a simple job, in practice a number of complications make it almost impossible.

Bidet Plumbing

• According to the experts at cornerhardware.com, the normal drain size for a bidet is 1 1/4-inch, while the normal drain size for a toilet is 3 inches. To flush away solids, a considerable volume of water must be dumped into a toilet bowl, from the cistern, in a short period of time. This would back up when bottlenecked by the preexisting 1 1/4-inch bidet waste pipe. At best, this would result in an extremely slow drain time with the solids remaining in the bowl; at worst, the toilet would overflow and sluice waste into the bathroom.

  Further, like any other sink, bidet waste-water connections must have a “U”-bend. In most applications the “U”-bend is of necessity below the floor because, unlike a regular sink, the bidet is fitted directly to the floor. Excavating and removing the “U”-bend so that new waste-water connections can be made is a large project.

Floor-Mounting

• A bidet’s drain connection and mounting hardware will almost certainly be different from that required to fit a toilet. The floor mounting flange -- sometimes called the “wax ring” -- will be of a different size, and is likely to be closer to the wall the appliance is fastened to than is required to accommodate a toilet with a cistern behind it.

Fittings

• Another potential problem is that the bidet was probably manufactured for the European market, meaning the connections to both the hot and cold feeds are likely to be metric. Blanking off the hot supply should not pose much of a problem; metric caps are available from most home improvement warehouses. Joining the cold water feed for the toilet to a metric pipe may prove more difficult -- if a metric-to U.S.-Standard fitting cannot be found, the metric item must be removed and replaced.