Frequently Asked Questions
Everything you'd want to know before fitting a urine separator. If your question isn't answered here, drop us a note via the contact page and we'll get back to you.
Choosing the right separator
What's the difference between the Compact and the Complete Urine Separator?
Both do the same core job — diverting urine away from the solids so your compost toilet stays odour-free. Both are handmade in Wales from solid 4 mm ABS, come in white or black, and are backed by our 10-year guarantee.
- Compact Urine Separator (the original) — our compact, lightweight insert, supplied to trim to fit. It connects to your own pipework, which makes it the go-to choice for self-builds.
- Complete Urine Separator — our full-unit design that fills the whole seat oval and looks more like a traditional toilet, with a removable metal filter that stops the pipework getting blocked. A slightly larger footprint.
If you're a DIY-er with your own pipework plan, the Compact is everything you need. If you'd prefer a tidier all-in-one with a built-in filter, the Complete is worth the extra. There's a fuller comparison in our how-to-build guide.
Will it fit my toilet?
Most likely yes.
- Compact: 170 mm wide × 283 mm long × 128 mm deep.
- Complete: 330 mm wide × 285 mm front-to-back × 130 mm tall.
Both fit under standard toilet seat platforms — just check your seat hole has room for the separator's depth below it. The Compact can also be trimmed down for an awkward space (see below).
Does it work for both male and female users?
Yes — the shape is designed so that both male and female users naturally direct urine into the front collection bowl when seated. This is the outcome of years of research and customer feedback. For men, if there's any contact with the plastic, lifting the seat slightly with a thin spacer solves it.
Does it work for children?
It does, with a couple of caveats. Younger boys may need a reminder to sit. The separator catches urine when seated, and the position works comfortably for children.
Installation
How do I install it?
The separator sits underneath your toilet seat platform and is fixed in place with screws (or runners). Position it so the front collection bowl fills the front third of the toilet seat hole. The outlet connects to standard 1¼" (32 mm) waste pipe — the same fittings you'd find at any plumbing merchant.
We've published a step-by-step install guide with photos, and a fuller how-to-build-a-composting-toilet guide covering pipework, chambers and ventilation.
What pipework do I need?
The tapered outlet (30–35 mm) fits standard 1¼" (32 mm) push-fit or solvent-weld waste pipe, as well as 32 mm flexible pipe — the white plastic stuff from any DIY shop or plumber's merchant. If push-fit feels snug, lightly deburr the inside edge of the pipe or use a 1¼" connector and it slips on easily. You'll also need a container or soakaway for the diverted urine — most customers use a jerry can, a sealed tank, or a pipe run straight to a soakaway.
Can I cut it to fit?
Yes. The 4 mm ABS trims easily with a jigsaw, a multi-tool or an angle grinder with a metal-cutting disc. The Compact in particular is designed to be trimmed to suit a custom seat or a tight space.
Can I fit it in a campervan, boat or tiny house?
Yes — these are some of our most common use cases. Customers use our separators in vans, narrowboats, tiny houses, off-grid cabins, glamping sites and allotment sheds across the UK and worldwide.
Where does the urine go after it leaves the separator?
That's up to you. The most common options are:
- Jerry can / sealed container — emptied periodically. Best for vans, boats and indoor toilets.
- Soakaway — a gravel-filled pit that lets urine soak into the ground naturally. Best for off-grid or garden setups.
- Diluted as fertiliser — urine is high in nitrogen and, diluted 10:1 with water, makes excellent plant feed.
Using your separator
Does it really stop the smell?
Yes — and it's the single most important factor in any composting toilet. The smell associated with compost loos comes from urine and faeces mixing together, which produces ammonia. Separate them at source and the smell disappears.
How often do I need to clean it?
The smooth, high-gloss surface is designed for easy cleaning — a quick rinse and wipe-down weekly is plenty for most users. Every so often you can lift it out entirely for a deep clean, which is why it's fixed with screws rather than glued in. The removable metal filter on the Complete also lifts out for rinsing.
What do I do with the collected urine?
If you have a garden or allotment, diluted urine (about 10 parts water to 1 part urine) is a fantastic free nitrogen fertiliser — particularly good for leafy greens, brassicas and fruit trees. Apply it to the soil rather than the leaves, and never use it neat. Otherwise it can go to a soakaway or down the foul drain.
Buying & delivery
How long does shipping take?
We dispatch every order within 24 hours. UK orders typically arrive within 2–3 working days on a tracked service. International shipping varies by destination — usually 5–14 working days. See our shipping & delivery page for full details.
Do you ship to the EU?
Yes — we ship directly to all 27 EU member states, with VAT included at checkout. Because We-Pee is IOSS-registered, your local VAT is collected when you order, so there are no surprise customs fees or handling charges when your separator arrives. EU delivery usually takes 5–10 working days, with tracking on every order.
Can I return it if it doesn't work for me?
Yes — we have a 30-day return policy for unused separators in their original packaging. See our refund policy for full details. If something has gone wrong — wrong fit, damage in transit — get in touch via the contact page and we'll sort it.
Materials & durability
What is it made from?
Solid 4 mm ABS — a tough, high-gloss plastic with a smooth, easy-clean surface that keeps its colour and shape for years. Designed and handmade in Wales, from materials chosen for longevity in damp toilet environments.
How long does it last? Is there a guarantee?
Every separator is backed by our 10-year guarantee. In practice they last far longer — many of our earliest customers from 2009 are still using their original separators. With normal use and basic cleaning, there's no reason a We-Pee separator shouldn't last decades.
Is it sustainable?
The plastic is durable rather than biodegradable — and that's by design: a separator that lasts a lifetime keeps far more material out of landfill than one that breaks down in a few years. And the whole point of the product is to enable composting toilets, which dramatically reduce water and sewage waste compared with flush systems.
Still have a question?
Drop us a line via the contact page. We're a small team and we read every message — we're genuinely happy to help with anything from product fit to compost toilet design advice.