You may wonder how a a toilet takes up such little space. The answer is simple: put the tank in the wall! Before now, there wasn't a system that would allow this to happen with 2x4 studs, but now there is. If square footage is important to you, checkout the innards of this system!
If you've ever wondered where they hide the tank in a wall mount toilet, wonder no longer. Geberit, known for making beautiful and minimal toilets, has created a new tank and carrier system that fits inside a standard 2" x 4" wall, allowing it to fit in smaller spaces and take up less room in smaller homes. Previously there were plenty of carrier systems designed to fit into a 2x6 space.
Bonus: It has a dual-flush valve for 0.8 and 1.6 gpf. But like all carrier models, it doesn't come cheap, and has a sticker price of $570.
(Image by Geberit)
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What if I need to fix the tank?
From what I understand, they've been making these for a long time, they just hadn't made it the the US before. Something about the way we build walls, I think. Anyways...as to repairs, there is an access panel.
They have been making these for a long time yeah, glad you're able to get them now, they're great. I really had no clue nobody made them in the States.
@herms: If something breaks inside the wall you just remove the flush button, fix whatever the problem is and put it back on.
If you're just building a new home you can install it into the wall, otherwise you build this 15cm deep x 120cm high drywall (just like in the photo) and voila. Love them. They run between $250 to $300 here.
These are the most common toilets in Denmark. Especially, in the small bathrooms of Copenhagen, however when they need to be fixed you're typically removing wall to do so. When our toilet broke just a few months ago the first thing the plumber asked before giving us a price, was if it was 'built in'. As embryoconcepts mentioned, there are ways to creatively build access panels. Which would be a more long-term solution.
If you're really tight on space, fixing drywall to get to a periodic toilet tank repair seems a reasonable tradeoff.