Considering switching from a floor mounted to a back outlet toilet in your UK home? Discover installation, benefits, and compliance with UK regulations for…
Ever looked at a standard toilet and thought, "There's got to be a better way to handle this"? For decades, the humble floor mounted toilet has been the default. A back outlet toilet, on the other hand, sends waste directly into the wall, a simple change in direction that makes a world of difference, especially in a compact bathroom.
A standard floor mounted toilet has a waste pipe that goes straight down into the floor. A back outlet toilet, sometimes called a rear outlet toilet, does exactly what it says on the tin: the waste pipe goes horizontally out the back and connects to a soil pipe inside the wall explains the fundamental differences and benefits of back outlet toilets compared to traditional floor-mounted models.
Why does this matter, especially in the UK where our bathrooms can be, shall we say, 'compact'?
But it's not a simple swap. Here's a quick rundown to help you decide.
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| Feature | Floor Mounted Toilet | Back Outlet Toilet |
|---|
| Aesthetics | Traditional, visible cistern & pipes. | Modern, minimalist, hidden cistern. |
| Space | Takes up more floor space. | Saves floor space, ideal for small UK bathrooms. |
| Cleaning | Awkward to clean around the base and pipes. | Simple to clean underneath (wall-hung) or around. |
| Installation | Simpler, connects to existing floor waste. | More complex, requires a wall frame (carrier system). |
| Maintenance | Easy access to all parts. | Access to cistern is via a flush plate; can be fiddly. |
| Cost | Generally lower initial cost for unit and labour. | Higher cost for the unit, frame, and installation. |
Right, so you're sold on the clean look. Before you start knocking holes in walls, let's talk plumbing system. In the UK, the biggest hurdle is often the soil pipe. In many older homes, this main waste pipe runs externally. Connecting a back outlet toilet means running the new waste pipe through an external wall.
If you're lucky, the soil pipe is internal. The key is ensuring you can achieve the correct 'fall' or gradient for the drainage pipe, letting gravity do its job. Get this wrong, and you'll be getting acquainted with your plunger far too often; the specific gradients are laid out in the UK Building Regulations Approved Document H: Drainage and waste disposal.
You also need to comply with other parts of the Building Regs. Part G (Sanitation, Hot Water Safety and Water Efficiency) dictates everything from providing sanitary conveniences to ensuring the plumbing system is hygienic Approved Document G: sanitation, hot water safety and water efficiency. Meanwhile, Part L (Conservation of Fuel and Power) covers water efficiency, legally requiring new installations to have a dual-flush mechanism, typically 6 litres for a full flush and 4 litres or less for a partial one Approved Document L, Volume 1: Dwellings.
This is not a casual Saturday DIY job unless you really know your stuff. I've seen enough botched jobs to know that a wobbly toilet or a slow leak behind a freshly tiled wall is a special kind of misery. The secret weapon for a solid installation is the carrier system: a sturdy metal frame bolted into the wall or floor that supports the toilet and houses the concealed cistern.
soil pipe? Can you achieve the necessary fall for the new waste connection?soil pipe accessible for a horizontal connection?carrier system rated for the expected weight?Years ago, finding a back outlet toilet in the UK was a specialist task. Now, most major bathroom suppliers and builders' merchants stock them from brands like Geberit, Grohe, and Roca.
The main long-term issue is maintenance. Access to the hidden cistern is through the removable flush plate, a bit like performing keyhole surgery explains the fundamental differences and benefits of back outlet toilets compared to traditional floor-mounted models. My advice? Don't buy an obscure, unbranded model just to save a few quid. Sourcing replacement parts in five years will be a nightmare. Stick with reputable brands where you know you can get spares.
A well-installed system from a good brand should be very durable. The frames are incredibly tough, and the pans themselves are just as robust as any floor mounted toilet. Most problems arise from poor installation, not product failure.
So, is it worth it? Switching to a back outlet toilet is a smart way to reclaim space and modernise a bathroom, especially in typically sized UK homes. It's a more involved job than a simple swap, but do it right, with a quality carrier system and a professional installation, and you'll have a sleek, easy-to-clean feature that adds real value. Just don't cut corners, or you'll be dealing with a leak inside a wall you just paid to have tiled.
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