What is the minimum toilet room size?

Ben2065

Hi everyone,

I am reconfiguring my floor plan and considering making a very small toilet room with small hand basin. The room would be aprox 76-80cm wide and would be 1.4m long. Only one of the long stud walls needs to be made (remaining 3 walls already present) and I am hopeful I can set up the studs on their sides (45 instead of 90mm thick) as well as lining the toilet room with blue board instead of gyprock) to save a few cm thickness. Just checking if this is pushing space too much? Is there a building code minimum size for a toilet room? I obviously would be getting a plumber in to do the toilet and basin plumbing install but don't want to arrange quotes etc if the space is too small. The toilet would be a P trap toilet with wall mounted cistern and would be planning to have a wall mounted hand basin with exposed plumbing to maximise space. Please be aware my sketch is just that (not perfectly to scale). Many thanks for your advice everyone.

Cheers,

Ben

MitchellMc

Hi @Ben2065,

Anecdotally, I've found references to half bathrooms, or powder rooms, which consist of a toilet and a basin having smaller size requirements than standard bathrooms at around 1.5 to 1.8 square metres. Ensuite bathrooms, or bathrooms attached to a bedroom, often have a minimum size of around 2.2 to 2.5 square metres. For half bathrooms with rectangular floorplans, the minimum layout is typically 1.4 x 0.95 metres. However, I'm struggling to verify that against National Construction Codes (NCC), as they don't appear to be forthright with actual minimum size requirements, if there are any. I'd suggest that it would be best to discuss with a builder whether any minimum requirements are set in the NCC. 

For ease of use, 900mm width is typically what you'd aim for.

Please let me know if you have any questions.

Mitchell