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Was it a good idea to buy a composting toilet?

We have just finished having a new bathroom fitted and as part of the changes we have installed a composting toilet to replace the 50 year old conventional toilet that was there when we moved in.

Reactions to this so far have ranged from “You’re completely insane.  That’s disgusting!” to “What a great idea! More people should do that“.  But the most common reaction is simply “Why?

Well, the reasons are fairly simple if you look at them rationally.

Reasons to buy a composting toilet

  1. An old style toilet uses about 13 litres of water per flush, and gets flushed about 5000 times per year according to Waterwise, so removing the flush is potentially saving around 65,000 litres a year of clean drinking water
  2. It takes a huge amount of energy to clean and pump that 65 tonnes of water to and from your home each year
  3. Water has a high thermal mass.  Each time you flush, the water from outside (cold) gets pulled inside and then absorbs heat from the room before you flush it back outside again, taking the heat with it.  Check out this analysis in Cold House Journal comparing the (unknown-to-most) evil of winter toilet-flushing to the (extremely well-known) evil of “letting all the cold air out of the refrigerator.”  In simple terms, imagine heating literally tonnes of material from outside winter temperature to indoor room temperature – that is the energy you are flushing away.
  4. Human waste (like any animal waste) is extremely nutrient rich.  We live in a world where soil fertility is rapidly degrading, and every day we are converting rich nutrient dense fertiliser into toxic sewage by mixing it with water and toxic cleaning chemicals.  It just makes sense to stop doing that and return the nutrients to the land in their pure form.
  5. We live in a society where we are always completely shielded from the reality of our own impact on the wider world.  In the case of toilets, we just flush and it goes away!  A composting toilet is a really valuable educational tool in helping us understand how much waste we produce, what it is and where it goes.  It also makes you think about the other things that you flush down the loo without a thought such as toilet paper, food leftovers and cleaning chemicals.
  6. A composting toilet can be installed anywhere, whereas a conventional toilet is limited to the position of the waste outlet in your bathroom, which is quite limiting if you want to change your bathroom layout like we did.  It is also a great option for buildings that don’t have a mains sewage connection as it is an alternative to a septic tank.

So perhaps a better question to ask is “Why not?” and I can think of a few reasons for that too.

Reasons NOT to buy a composting toilet

  1. People are uncomfortable with the idea of keeping or ever seeing their own or anyone else’s poo (as a side note, it is interesting that Poo still doesn’t seem to be in the dictionary!)
  2. Most composting toilets are expensive (although they could well pay for themselves in reduced water, sewage, energy bills and garden compost)
  3. ALL composting toilets that I have ever seen are ugly, which is something that I think the manufacturers need to urgently address

The first issue is purely cultural and if composting toilets were more common and well designed then I think this could easily change.  The price is largely due to the fact that they are produced in small numbers, which would change if they were more popular, which means some people need to suck up the cost and buy them now to give the industry a boost.  The final is a challenge for the manufacturers who seem to be living in a utilitarian bubble and haven’t realised that bathrooms are places that people spend a lot of money to make beautiful and that they are competing against a lot of very high quality and elegantly designed conventional toilets.

We did a lot of research to find the best toilet for our needs and settled on the Swedish designed Separett Villa 9000, which we bought from the very friendly guys over at

We’ve had it now for nearly a month and I thought it worth writing a review, since I can’t find any other reviews for this toilet online.

Review of the Separett Villa 9000 Composting Toilet

I’m going to divide this review into the key areas that I think are relevant for a composting toilet – User Experience, Style, Smell, Noise, Waste, Installation and Maintenance.

User Experience

The user experience is something that I have been really impressed with.  The guys at Separett have been rather clever in figuring out that no matter whether you are a guy or a girl, when you sit down on the loo your urine comes out the front and the poo plops out the back.  This has allowed them to seperate the urine and faeces (I’ll explain about that later) without any inconvenience to the user.  You just sit down and do your thing like you normally do.

Some women might need to sit a little further on the sit than normal, but they have even included a little extension piece that can be clipped on if you find that to be a problem.

The thing that many people are worried about is seeing the poo underneath them, but the toilet hole has a trapdoor keeping it closed that automatically opens when you sit down, and thanks to the urine funnel at the front it is near enough impossible to see down the hole between your legs.  The only time that you can really see it is if you stand up to wipe your bum and the have to manually push the seat to open the trapdoor to throw the paper in.  This part of the process isn’t ideal and although it is not a big problem I do think that it would be a big selling feature if the designers could find a clever solution for this.

If you have kids, the toilet even comes with a special baby seat that fits on the top and allows you to use it during potty training, which I thought was a nice touch.

One big difference compared to a normal toilet is that men have to sit down to pee.  That trap door won’t open unless you sit down, and even if it did you’d probably piss into the poo chamber instead of the urine funnel, so the trapdoor rather cunningly forces men to sit down.  Men might find this a bit annoying, but I think for the ladies of the house this is actually quite a big selling feature.

Finally, one thing that seems a little strange at first is that you can’t flush the loo.  It is amazing how strongly some people (and it does seem to be more with women so far) have an irrepressible urge to flush the loo.  If you live with it then you get used to it soon enough, but it is a bit odd for guests.  I think they should add some sort of pretend flush handle that makes people feel that they have somehow finished their business.

Overall, I am really impressed with how well the design works from a user perspective and how easy it i to adapt to, since you use it almost the same as a normal toilet.


When it comes to style I don’t know whether to be cruel or kind.  On the one hand, the Separett Villa 9000 is by far the best looking composting toilet that I have seen anywhere.  In fact, it is one of the only ones that I have seen that actually looks like a toilet at all.  So I have to give the guys and girls at Separett credit for being at the front of the industry in this respect.

Having said that, if you compare it to even a cheap conventional toilet then it doesn’t fare so well.  To some extent it’s bulk it unavoidable and Separett have already done a good job of keeping it almost within the same footprint as a regular toilet, but the shape is bulbous and unrefined.

On top of that there are little details that just seem careless.  The toilet seat is flimsy and isn’t even the same shape as the toilet, which looks ugly, as if they just got some cheap plastic toilet seats from China and clipped them on.  There is a big blue metallic badge with the Separett logo in pride of place, which looks like the sort of naff 1980’s badge that you expect to see on a disability aid (not that that is any more excusable) rather than in a bathroom and lastly the trap door and the seal around the vent pipe are both blue, which isn’t the end of the world but I can’t imagine that it goes with the colour scheme of most bathrooms.  Something more neutral would have been a much better idea.

The other problem aesthetically is that the whole unit is made of plastic, and it looks like plastic.  Not the type of high quality, tactile plastic that you see on a iPhone or even a nice plastic bath, but more like the type of plastic that you expect to see on a bucket or gutter pipe.  It doesn’t look that bad, but you can’t escape that fact that it shouts out PLASTIC!


Having finished my little rant about the styling, here is the good news.  It doesn’t smell – at all!  Even my Mum who has the world’s most sensitive nose for unpleasant smells didn’t notice anything when she visited.

We did have a problem in the first few days because the vent pipe hadn’t been properly sealed, but we got this sorted and it has been fine ever since.

By separating urine from faeces, the poo is able to dry out and start decomposing instead of turning into the rancid toxic sludge we usually expect, so it doesn’t produce as much smell as you would expect.  On top of that, the toilet has a low power fan unit to constantly evacuate any smells to the outside.  It has two speeds, so you can boost it i required but so far this has not been necessary.  The fan uses about 280 watts per day, which isn’t ideal but could be worse.  They also offer a solar powered option on the fan too.


There are really only two aspects to the noise.

First is the thonk that the trapdoor makes when you sit down.  It isn’t a big problem and certainly less than the noise of a conventional flush, but it does somehow irritate me a little that the manufacturers haven’t found a way to just soften the noise a little.

The other noise comes from the fan, which is fairly quiet like a normal bathroom extraction unit.  Most of the time we don’t notice it at all, but if we leave the bedroom and bathroom doors open at night then the hum does penetrate the silence and we end up getting up to close the door.  Not a big deal though.


As mentioned, the Villa 9000 separates urine from faeces.  This keeps the faeces dry so that it doesn’t smell as much but also allows it to compost, which it won’t do if it is soaking wet.  At the same time, it keeps the urine clean, which can be piped off and used as a rather potent plant fertiliser.  This requires the use of some sort of storage tank (which is an optional extra that we haven’t bought – yet) and is a really good idea.  I like us you don’t get that all organised you can just pipe it down the drain.

Emptying the toilet is really easy.  You just pop the top open like a car bonnet, stick a lid on the bucket to keep the smell in while you remove it (this does require a few seconds holding your breath) and then you can take it outside to either compost inside its own bucket or empty it into a larger composter.

The only issue that we have found so far is that it fills up a lot faster than we expected.  When I asked Separett before we bought it they said that we should get about 1-2 months out of a single bucket.  In practice it is more like 7-10 days.  That is a big difference!  There are probably three main factors for this. Firstly, we work from home a lot, meaning that the toilet gets more use. Secondly, we have had a lot of guests since it was installed and thirdly, we eat mainly high fibre plant based foods, which does significantly increase the bulk of your poo.  We asked Richard at about this and he said that the easiest option is to use a HotBin composter, meaning that you can empty the buckets into the large HotBin and compost it all down in just 90 days, keeping the number of buckets required down to a minimum.  We’re going to try this and will post an update in a few months time.


Installing the Villa 9000 is relatively simple and they have an excellent YouTube Video to show you how to fit it.  Ours was a little more tricky because we didn’t have it on an outside wall and had to vent it up into the roof, but it was nothing that our plumber Mike Kinna couldn’t handle.  The best thing is that there are not many limitations on where you can fit it.  We wanted to move the toilet to the opposite side of the room to the old toilet for a more space efficient and practical layout, but moving the waste pipe for a conventional toilet is a big job.  The Villa 9000 can be fitted almost anywhere and the vent pipe can either go through a nearby outside wall or up into the loft cavity and through the tiles or an external wall.


As far as I can see, there shouldn’t really be any maintenance other than emptying it.  Our plumber did say that there could be a risk of the urine pipe scaling up with mineral deposits so we have been making a point of rinsing it out from time to time.  You can also get eco friendly anti-scaling agents that you can rinse down to be on the safe side.

The instructions also say that the filter on the fan should be cleaned out from time to time, which is a pretty small job.

Other than that, as long as the fan keeps on running then there isn’t really anything to maintain, which is great!


Overall, I have really impressed with the Separett Villa.  I might not be in love with its looks, but it is a really clever and simple design that makes using a composting toilet a simple, pleasant and familiar experience, and that is really all you want.  If you are thinking about taking that huge leap of faith and installing a composting toilet then I think this product probably is one of the best on the market and definitely a good choice.

So was it a good idea to buy a composting toilet?

So far, the answer is yes.  I’ll update this review in a few months time to let you know if I’ve changed my mind!

UPDATE! 21st May 2013

So it has been about 8 months since we had the composting toilet installed and I am pleased to say that we are not regretting our decision.  It has been an interesting learning curve for us and a point of interest for many visitors.

So what are our highlights, lowlights and interesting experiences so far?


  1. Firstly, it has been a fascinating learning experience to see whether it is really practical and it has been great for us, so the answer is yes!
  2. We have been surprised how many of our guests have been really fascinated by it and even in some cases had “toilet envy”.  This is despite its lack of aesthetic charm.  Don’t get me wrong, not everyone likes it, but the overall feedback has been far more positive than we expected.
  3. Having got off to a bit of a slow start, we have found that it seems to compost down really well on the regular compost heap if we throw a load of cut grass from the mower on top of it each time.


  1. We have had a few cases where people ignored our instructions and thought they knew better.  Two men decided to stand and pee, which is both stupid and messy, and a lady who couldn’t handle the idea of not flushing so poured water into the solids tank.  Doh!!  We have put a sign on the inside of the lid with some more blatant instructions.
  2. We have had a bit of trouble getting composting to work.  We have found that if you leave it in the plastic tubs for 6 months as instructed, then nothing much happens.  The HotBin is great idea in concept but we couldn’t get it to reach the high temperatures required.  We think both of these may be because the contents are too wet and so this is something that we need to figure out.  However, as mentioned above, it seems to be working pretty well in the normal compost bins.

Other Experiences:

  1. We have been averaging about 2-3 weeks between empties.  This hasn’t been a problem at all but it is interesting that it is well below the estimate that Separett gave us before we bought it.
  2. There have been a few occasions where we got some smell leaking into the bathroom.  Whenever this happened, we found that it was because the air filter on the extraction fan had clogged up with dust.  A simple rinse of the filter fixed it each time.
  3. The compostable bags help to keep the buckets clean but they tend to start composting before you empty it and so they don’t work as perfectly as you’d hope.  At least they really do compost though!
  4. Some people don’t like the fact that if you manually open the flap to throw toilet paper down, you can see the poo inside. I agree, but a simple change of habit fixes that.  Just tip, wipe and check without standing up, instead of stand and wipe.  It turns out that the population seems divided down the middle between these two techniques and most people don’t realise that there is more than one way of doing it.  Who would have thought?
  5. We have been a little concerned that the urine pipe could scale up if we are not careful so we have been regularly pouring some water down the pipe and sometimes flushing down some eco-friendly descaling fluid.  It seems to be fine so far but worth keeping an eye on it.  The toilet did come with a blue block that goes in the urine funnel to help solve this problem but I have resisted using it because I didn’t want it to feel like a public urinal.  I’ll probably test it out at some point though.

UPDATE! 25th January 2015

Since we installed the Separett Villa composting toilet I have been keen to find out how much water we actually saved in reality, as oppose to theory.  It has been hard to work out because our water company do meter readings very very infrequently and so I have had to wait a long time to gather enough data to actually know for sure.  But finally that day has come!

Before we installed the composting toilet we were using 192litres per day (already well below average for a 2 person home in the UK – average is about 270litres/day).  We are now using an average of 117 litres per day, a reduction in water use of 75 litres per day or 39%.  That is a seriously good result in my mind as it will save around 27,000 litres of clean tap water every year.  It is also worth noting that we changed our shower at the same time and the new one, despite the water saving head, certainly uses more water due to the more powerful pump.  The toilet has probably therefore saved even more water than these figures show.

58 thoughts on “Was it a good idea to buy a composting toilet?

  1. I have just installed (but not yet used) a Separett and found this a really, really useful summary of how it works and what to look out for. We bought ours from Richard as well and found him helpful and knowledgeable. Thanks for taking the time to write such a detailed report on your experiences.

    Perry Healey

    p healey

    • Hi Perry

      Thanks for the comment. I’d be fascinated to know how you get on with it in terms of both the toilet itself and the composting side of things. Please do feel free to post an update or contact me if you have any questions.


      Tom Greenwood

  2. Interesting review! I enjoyed reading it. I have considered getting a unit like this, although I am concerned about the amount of heat that would be lost in the winter if the exhaust fan is running 24/7.

    Oh, one small thing I noticed: it’s not possible to have a number of watts per day. Perhaps you meant 280 watt hours (or 0.28 kilowatt hours) per day?

    Anyway, thanks again for the review!

    Brandon Thomson

    • A few corrections…yes, they have the watts wrong. I’m in the US and our model uses 2.5 watts – almost nothing. There is a different model that uses 17 watts, still almost nothing. Second, I’m in plastic manufacturing and the comments about plastic are incorrect. You can’t just use a different type of plastic, such as used by an iphone (and that would have no strength, even if it would work – it’s not “better” plastic.). Your choices are injection molding and rotomolding. Injection molding is used to keep the cost down. People see plastic and they think cheap, but I would estimate that it cost over $500,000 pounds to build this toilet, in molds alone, and that is before production even began. Ours lasts 3-4 weeks for a family of four before emptying. We only use one small bucket, and dump the whole thing in a large compost bin in the back yard. We use two bins. When the first is full we start using the second. When the second is full, the contents of the first goes on the plants.


      • Hi Brad. Thanks for your comments.

        Our toilet uses 280 watt hours per day (yes, typo in the article), which is about 12 watts. There could well be some variation compared to your model, but we are in agreement that it isn’t much.

        Regarding plastic, I am simply commenting on the user perception of the product and that it feels cheap to have a big block of white injection moulded plastic in the bathroom. To give context, most toilets are porcelain or made of some form of glass reinforced plastic, both of which normally have a much better surface finish and appearance. I don’t doubt that Separett have legitimate reasons for the manufacturing method they chose, but I also have a legitimate reason for disliking the product from an aesthetic point of view. It doesn’t matter how much money they spent on molds, the fact is that if it looks cheap, it looks cheap.

        On most other counts I think it is a great product. Glad you are getting on well with yours.

        Tom Greenwood

  3. Hi Brandon, yes it is 280 watt hours. Well spotted!

    I have been wondering about the heat loss from the fan aswell. It obviously depends on your local climate and also what you are replacing (if anything), such as a water flush toilet or an existing bathroom extraction unit. Not to mention the behaviour change that could result from opening the window less in the winter. There are a lot of variables unique to each situation.

    Tom Greenwood

  4. Thank you for this article. We cant find any user experiences for this toilet. We will try the Separett Villa and I will send you our experiences and ideas.

    Lukas Dedina

    • Sounds good Lukas. Let me know what you think if you do try it.

      Tom Greenwood

  5. I use a Sunmar in the USA, mixed feelings about it. On one hand, I love having a composting toilet! On the other hand, the quality is not so great and parts keep breaking. I really like the look of the Separett and appreciate this review. I have the same issues as mentioned above, it needs emptying way more often than expected. I use a large compost bin outside and add all the kitchen waste. I have beautiful flowers! A trick to faster composting is to add some composting worms to the bin, the kind people use as kitchen ‘pets’. They absolutely adore the waste!


    • Thanks for the comment Shelagh. Great tip! We actually used to have a wormery but sounds like it is time we get those worms back!

      Tom Greenwood

  6. Thank you so much for your review. Here in Australia I have found that sellers of composting toilets tend toward being ‘salesmen’ & tell you what you want to hear. Having reached my own understanding that urine separating toilets which dry/dessicate the solids are really different beasts to those which actually compost, I have become more enthusiastic about getting one for our situation. Although in the longer term we may choose to compost as you have, our prime reason for wanting one is to avoid the considerable cost of installing a septic system. I’m thinking that a deep’ish disposal hole to dump the removed bags will suffice on our rural property, & piping the urine into the grey water soak away trench. When the solids disposal hole eventualy gets close to full it can be filled in & a tree planted in it. All previous reviews on other composting toilets have left me feeling that one needs to be a skilled compost ‘artist’ to make the thing work, & that if those skills are lacking the result is likely to be at best disappointing & at worst most unpleasant. Finding the Separett Villa & reading your review has changed that. Thanks again I think my decision is now made.


    • Really glad to here that you found it useful Cuppa! A composting toilet is definitely worth thinking about as an alternative to a septic tank and as you say, the separating of solids and liquids makes it really simple even if you don’t want the compost.

      Tom Greenwood

  7. I have owned my Separett for over a year and just love it! I had a Sun-Mar before, and I did not like it at all – no way a family of 3 can use it full time and have it actually do any composting in the finishing drawer. It was just a giant, ugly, loud bucket toilet that was constantly overflowing with liquid waste. Really gross. But, I love the Separett. **We DID have a problem with the scale build-up in the urine tube. Tried to unclog it with bio kleen drain opener to no avail. Eventually ended up getting a hand-held roto-rooter device at Home Depot for $25 that did the trick! But, it will probably be ok for you if you rinse regularly.

    I have found it to be a bit loud, but we have never installed the mounting bracket, as we bought it used and did not come with the bracket. I assume once I get the bracket installed, that might cut down on the vibration volume, but I fear I will always hear the fan through the wall. It’s ok, though.

    We simply empty the bucket in to our compost pile and let nature take it’s course. Once we fill up a compost bin made from 4 pallets and chicken wire, I simply cover it with a tarp for a year, and viola, beautiful compost! I always throw some straw on top of both the bucket contents and our kitchen waste to keep any smells out and to add some bulking material to the mix. I NEVER turn the compost, just add layer upon layer like a lasagna. The best thing to use to help break things down are Black Soldier Fly Larvae – better than worms! Amazing little critters, and their pheromones keep house flies away!

    Thanks for the review and good luck to ya!


    • Thanks for sharing your experiences Eric! Our urine pipe has been OK so far because we rinse it regularly but there is a small amount of scale in it and I have wondered if this could become a problem long term. I’ll look into the roto-rooter devices – I’m sure something like that must be available here in the UK.

      Tom Greenwood

  8. I am currently considering the 500 kit. It is for a converted bus and I don’t want to deal with the hassle, space and mess of a black water tank. Having multiple buckets will solve the issue of changing and dumping while on long trips.

    B. Gleason

    • Great idea!

      Tom Greenwood

  9. Tom, Thank you for your candid descriptions in your “experience” section. I have tried to find answers to some very intimate and “real” concerns with using this toilet. I hope these questions are not too graphic but I honestly want to know:
    All reviews say it is odorless, I like that you mention there IS odor when you change the bucket. My guess is it would be no worse than emptying a diaper pail. Is that the case? Have you tried putting a scoop of grass clippings or compost boosting material through the trap door before opening the toilet to change the bucket? Next, let’s face it “fresh” waste has an odor, a strong odor. The odor quickly decreases as it dries. That is why the separation of the urine works so well to keep the toilet odorless. However, what about when you use the toilet immediately after someone else? Their waste will still have a strong odor and now you are sitting on the seat causing the trapdoor to open and allow that odor to come out. Is the fan powerful enough to prevent this from being an issue? I know if you use bathroom right after someone else then you deal with the odor they leave behind even when using a flush toilet bathroom. However, I fear the Separett would be worse as the waste is still present in the room. Is this an issue? Also, I am installing an exhaust fan in the ceiling above the toilet area for humidity control and to address the normal odor issue I described above. Will the fan compete with the Separrett fan causing the odor to be drawn into the room instead out the toilets vent pipe?

    Thanks again for this informative post!

    Polly Ann

    • Hi Polly, thanks for your questions.

      When emptying the bucket there is some odour. You are right that this is less when the most recent waste has had some time to dry out and also if you put some chippings, paper or other material over the top before opening it up to remove the bucket. Having had the toilet for over 1.5 years now, I’ve become quite quick at the emptying process, so it takes just a few seconds to pop the toilet open, put a lid on the bucket and then it is all sealed, so the smell that escapes if fairly minor, and then the fan keeps sucking so by the time I come back in with the clean bucket, the smell has generally been sucked away again. If you have a really sensitive nose then it could bother you, but hasn’t been a problem for us so far.

      When using the toilet after someone else we generally don’t smell anything and the fan does a good job at ensuring that the odours flow out through the vent and not into the room. The exception to this is when someone has a really terrible smelling poo, probably when ill or after eating something really dodgy. This has been pretty rare but it has happened a few times and we have simply put the fan on high speed, opened the window a crack and chucked some paper or chippings on the top through the trap door. If we are getting into details, then I can confirm that what people eat has a big impact on how much their poo smells. Fruits, vegetables and grains don’t smell much, but spicy foods, meat and junk food can be noticeably more whiffy!

      I should also mention that sometimes the toilet does give a bit of a faint whiff when we have a visitor using the toilet, which can be a bit awkward and we think it is caused by people letting some of their pee go in the back. Fitting the extension piece that comes with the toilet reduces this, as does telling people to sit forward a bit, and putting the fan on high speed just in case. Day to day this isn’t a problem but it happens occasionally with people who have never used it before.

      Regarding the exhaust fan that you will be fitting, I don’t know if it will cause a problem. We actually don’t have a ceiling exhaust fan in our bathroom. The house didn’t have one when we moved in and after installing the toilet we found that it does an adequate job (though not as quick as a dedicated exhaust fan) of clearing the room, so we decided to keep things simply and leave it as is. My guess would be that it wouldn’t be a problem though, since we often have air flow from doors and windows creating a draft through the bathroom and it has never caused the smell to increase. I think it is effective because the fan is so close to surface of the waste and in a closed unit, so there is little chance for the smell to get diverted. It is also the reason that the mesh filter on the fan can clog up though, so keep it clean. If ever there is a smell, the first thing I check is the filter. A quick rinse often sorts it out.

      Tom Greenwood

  10. Hi, we are looking at installing this on a boat.

    How often are you changing the container? I was quoted several months. I am a bit concerned if this is actually a few weeks.


    • Hi Hugh

      I think that the manufacturers estimates are a bit optimistic. It is worth remembering that usage levels can vary massively so it is worth reviewing your unique circumstances. In our case we are emptying every 2-3 weeks generally. There are two of us in the household, it is our only toilet, we work from home most days (this makes a big difference!) and we eat a very high fibre vegetarian diet (which also makes a huge difference!). We also have a lot of guests visiting and using our toilet. So I think we are probably a worst case scenario in terms of how quickly it fills up and many people would probably find that they could empty it less frequently.

      Tom Greenwood

    • Hi Hugh,
      Can I strongly suggest that you consider purchasing the Natureshead waterless composting toilet. The reason is that it is specifically designed for installation in boats. You should get 60 to 80 uses of solids before emptying and it only requires you to add a small amount of peat moss into the composting chamber before use initially. If first wipes are put into the toilet and the ‘polishing paper’ put into another container for landfill disposal or burning, then the use period is extended. Another reason for the choice is that it uses a small ‘computer style fan’ on 12 volt supply and this is quiet and runs for 24/7 and draws only .12 amps, or a little over 2 amps per day from your battery. The fan ducts the slightly earthy odour out through a suitable dorade fitting on deck, and keeps a negative air pressure on the composting chamber. After use the poos are agitated with a handle on the side and when mixed with the peat moss the contents become indistinguishable and odour is reduced, rather than the fresh stuff sitting in a pile. The urine is ducted into a bottle on the front of the unit for disposal as appropriate, overboard or to a dump facility/toilet on land. Owners of boats, motorhomes, holiday homes and tiny houses in New Zealand are finding these units ideal. They are manufactured in USA from HDPE and marine grade stainless steel. There is and agent in New Zealand as well as in the UK and Australia. You can check the USA site for sales and distributor addresses. Hope this works for you.
      Cheers, Alan

      Alan Morton

      • Thanks for the detailed advice Alan.

        Tom Greenwood

  11. Thanks for the info! We will be installing in a “mother in law” room in our shop.It will only be used every now and then for company. Will the fan need to be kept running after company has left for awhile? Thanks for the help. Rich


    • Hi Rich

      Sounds good. Yes, you need to leave the fan running whenever there is waste in the toilet. If you empty it after guests leave then leave the fan running for 5-10mins and it will suck out ay smell that escaped when you opened it fr emptying, but then you can leave it switched off as long as everything is clean. I recommend using the biodegradable bucket liners – they make it far easier to empty cleanly and also help prevent the plastic buckets from absorbing the smell.

      Tom Greenwood

  12. Tom
    Thank you for such a detailed account of your toile experience. I am looking to replace our RV fillet with a compost toilet.



    • Sounds great Lin!

      Tom Greenwood

  13. Thank you very much for your review! We are in the US and are considering a Separett for our Colorado tiny house. There are so many options out there, but this loo is at the top of the list. Thanks for all the details and the lengthy review. I was hoping we could get a month between bucket changes, but looks like 2-3 weeks is as good as it may get (which is still pretty good).
    I LOVE that the Separett has the urine drain in a separate location (outside) so I’m not emptying buckets of urine every other day.
    Thanks again!!

    Run Turtle Run (@turtlepacing)

    • Great to hear that you found the review helpful 🙂 Enjoy the running – must be awesome in Colorado!

      Tom Greenwood

    • Just a thought for you. The Natureshead is still an option. All you do is unscrew the bottle holder from the front and remove it and the bottle. This leaves a vertical pipe which you plumb through to the outside of your tiny house. Very simple to do. The Natureshead system is much better because it is actually composting the solids by mixing them with a carbon material – the sphagnum peat moss or alternative. By comparison the Separett is just a holding tank for raw solids like a ‘long drop’ toilet and therefore will have more smell. I know which one I would prefer. 🙂 Also, if you burn or bury the ‘polishing paper’ the Natureshead will give you over 60 uses before needing to be emptied.


      • Keep in mind, though, that any time you are storing waste for more than 2-3 weeks, you are bound to get an infestation of Fungus Gnats. I could NEVER get rid of the Fungus Gnats in my SunMar once they arrived. Sometimes I’ll see one or two when the Separett has been sitting there for 3 weeks, but as soon as I put the cover on and take it outside, they are gone! I would never want to compost anything at the location of the toilet. Composting happens outside with Black Soldier Fly Larvae, earthworms, and all kinds of other critters. You will NEVER get finished compost from a system in which you are always adding new material.


        • Hi Eric, Fortunately we don’t have Fungus Gnats in New Zealand but I guess we could get fruit flies (very tiny) in there. The Natureshead toilet actually has insect screens built into it both on the inlet air side and also on the fan side so the only way they could get in would be if you left the lid up or the trapdoor open. If the pee water is ducted away through a pipe it should have an ‘S’ bend water trap anyway to stop any bugs crawling back up it. Secondary composting is normal with any system because what went in there this morning will not be composted by this afternoon when you empty the chamber. At least with the Natureshead the solids are mixed with the peat moss and pretty unrecognisable, whereas with the Separett it is basically just a ‘dump’ in a plastic bag! Phew 🙁



      • Thanks for the comment. The Naturshead does look like an interesting product although I don’t have any experience of it personally.

        Similar to Eric, I am quite happy to empty the Separett regularly, keeping the inside clean and fresh and letting nature do the composting outside. I’d like to see a Naturshead in action though so that I can properly understand what it is like in practice. I’m sure there are pros and cons either way.

        Tom Greenwood

  14. G’day Tom & readers,
    It’s almost a year since I read your review here, & it was this which saw us decide to go with a s Separett Villa 9000. Well we finally bought one & it arrived today. I must say I’m quite impressed with it out of the box. Sitting on it is comfortable, although slightly taller than the ‘conventional’ toilets. The fan moves quite a lot of air even on the low setting but is much quieter than I expected.

    I will be connecting the urine pipe into our grey water system & am concerned about grey water smell coming back up the urine pipe. It will need to connect into the grey water pipe less than a metre before a grease trap (which can tend to get a bit smelly). I see in the accompanying leaflet a ‘u’ bend (water trap) is available as an optional extra although it is also advised to have a constant fall with the urine pipe. There is not a lot of height between the urine pipe outlet & the floor (a concrete slab in my case – pipe will exit through the wall) so not much gravity pressure to drain the urine if a water trap is used. My plumber suggested simply shaping the urine pipe into a ‘U’ or an ’S’. The Separett agent wasn’t keen on anything other than a continuous fall, but suggested the small diameter vent pipe tee’d into the urine pipe inside the toilet may be sufficient to prevent smells from the grey water.

    Soooo… has anyone used a water trap, or connected the urine pipe into the grey water without smell coming back through the urine pipe?

    We plan to have a ‘mandi’ alongside the toilet so we can ‘flush’ the wee after each use. Have others found this sufficient over time, or is it really necessary to use some sort of enzyme fluid or the Separett supplied blocks?


    • Hi Cuppa

      That’s very exciting news!! I really hope it works out well for you.

      We don’t have our urine pipe connected to a grey water system so I can’t share any experiences on that, but will be very interested to hear your experiences because we might do that in the future.

      Regarding flushing, we keep a bottle next to the loo and ‘flush’ it after each wee to keep things clean. We have never put any enzyme fluid down it and the only Separett block we have used was the free sample that came with the loo. However, after about a year I cleaned out the urine pipe with the pipe cleaner attachment on our Karcher pressure washer. It seemed to work really well but it did flush out a huge amount of mineral deposits (and taught me that I should cover my face before sticking a pressure hose into a urine pipe! hehe)

      Tom Greenwood

    • We only just purchased the Villa 9200 this week and are in the process of upgrading the bathroom and installing it but I noticed this comment… the guy we purchased ours from advised that Urine itself shouldn’t smell but when mixed with soapy water (grey water) then there was a possibility it would smell a bit funky. His suggestion was to have a separate drainpipe that discharges a short distance from the grey water pipe, or make sure that you put P traps in. If you use P traps then you would need to run heat traces for the winter.


      • Thanks for sharing this tip Rona!

        Tom Greenwood

  15. Thanks so much for this informative site. I did have one question about the venting – we are looking to put this in the basement for my mom, so it would be vented out the wall, it seems at about our height (to our backyard and underneath my bedroom window). Do you have any experience with any smells that might come out of that outside vent? I assume we could run it all the way up the house, but that seems a lot more involved and would be nice to avoid, unless the vent is at all smelly. Thanks again for all of your information on this!!

    Meg L

    • Hi Meg. Our vent comes out of the side wall of our house facing into the back garden. It is about 10ft above the ground and in the time we have had it installed, I have only ever had 2 occasions where I got a whiff of it, and it was only faint. I guess the higher you can vent it the better, but it is not noticeable the vast majority of the time in our case. I hope that helps.

      Tom Greenwood

  16. Thank you for the review on the Separett. I will be having one installed for my motor home. I found another short review, this person is saying they are having trouble with maggots. Have you ever experienced this?


    • Hi Jay. No we haven’t ever had any problem with maggots or any insect problems at all. I’m not sure why they would get this problem but I guess factors could include the frequency with which they empty the toilet, the climate where they are and possibly even diet, but I haven’t heard of this before so really don’t know.

      Tom Greenwood

  17. Excellent review that is much appreciated.

    My wife and I are seriously considering purchasing. Unfortunately, there is a double-hung window located on the wall directly behind the toilet location. This wall is the only reasonable means of venting available. Has anyone vented in a similar fashion? Do current users suspect that odor would be a problem?

    Thanks in advance for reasonable responses.

    Skip Slade

    • Hi Skip, I can’t comment on your specific situation but our toilet vents out of the wall about 2 feet directly above our bedroom window and we have never had any problem with odour when the windows are open.

      Tom Greenwood

  18. Can anyone tell me if there are any issues with cleaning the sides of the basin if poop doesn’t make it where it’s supposed to? I’m assuming you’d use water and a toilet brush to clean it as you would with a regular toilet but then that water would go into the poop bucket, which isn’t what you want. Please advise.
    We have used the Separett outhouse toilet seat adaptation for separating the poop from the urine at our cottage in Canada. It’s really reduced the normal outhouse aroma. It’s made such a difference that now that we’re ready to upgrade to an inside toilet and are naturally drawn to the Separett Villa.
    Thanks for your continued committment to helping people get the scoop on effective compost toilets.

    Jean Merritt

    • Hi Jean. Great to hear that the separation method has worked well in your outhouse too. In terms of cleaning, we find that the easiest way to clean the sides is to use a spray detergent and some tissue to wipe it down, then just throw the tissue in the toilet. By using a spray detergent instead of pouring water, the amount of water that ends up in the back is negligible. We tend to do a more thorough clean each time we empty the poop bucket, with the bucket out and the lid open.

      Tom Greenwood

  19. Hi Tom,
    Very helpful to read your review and comments as I’m about to order a Separett Villa and was researching more about the “clean aspect” of the toilet. My first concern is hygiene. Odour and insect/germ problems. Don’t get me wrong, i’m not a clean freak but I’m worried for practical problems. Does the trap door get in touch with the solids at anytime? How do you know your container is “full” – do you open the toilet and check it every now and then?
    Also, is it possible to add some soil/ coco fiber etc. to start the compost (and reduce the smell?). Have you tried adding something to it, instead of just having only the poo there lying for 3 weeks? Thank you.


    • Hi Marina

      We have not had any insect issues. Generally it doesn’t cause a smell issue, but the exception to this seems to be if the vent filters get blocked, which a quick rinse will fix, or if someone puts water into the solids section. In that case, emptying the solids into the compost and putting in a dry bucket is the quick solution.

      Regarding the trap door, it is pretty intuitive to use and yes, you just have to look from time to time. If you don’t empty it and let it overfill then eventually the trapdoor will touch, but otherwise it isn’t really an issue. The exception to that is in the event that someone isn’t feeling too well and has a “jet poo” that casts its spray wide 😉 But that would be messy with any toilet!

      Also, occasionally when we empty it we find that some toilet paper is actually outside the bucket. I think this happens when someone throws their paper onto the closed trapdoor and then opens the trapdoor. Generally it would just drop in but it can sometimes get thrown off to one side. If it is your toilet then you’ll learn how to use it correctly pretty quickly but these things can happen more easily with guests. Once every few months I remove the turntable from inside and give the inside a thorough clean out to keep it nice and clean.

      Regarding soil, coco fiber – yes you can. We haven’t ever put any soil in but we sometimes put coco fiber in and also wood chippings, which seem to work quite well. Again, these can sometimes make their way outside the bucket if you accidentally let them fall onto the trapdoor when it is not fully open and so an occasional clean out is a good idea.

      Tom Greenwood

  20. Hi Tom,
    I’m glad I found you here! I have a couple questions that I can’t find any answers for, or leads to on any search engine.
    I bought and am using the Separett 900 for my cottage, now small house. I got my plumber to attach the urine pipe to the existing grey water system (the compost toilet replaces a 13L old toilet). After one or two uses, I spray the urine ‘area’ with vinegar to keep it clean. It’s only been almost two months and no problems with smells. The plumber attached with a straight pipe, I think–no bends or curves to keep the smells down. No need for that.
    I live on the east coast of Canada so perjaps I should wait until I live in my cottage for a winter when opening the window will be an issue before I determine that a straight piping is OK vs a curved or bent piping!
    My vent is up through the roof, to keep with the building code; my plumber said the through the wall vent would not meet code.
    I wrapped the ABS piping with bubble wrap and my carpenter built a box to cover the ABS and insulating wrap. The box comes also with shelves so the toilet plus shelves and box make for a nice looking unit!
    No trouble with odours from the toilet at all. I actually have a covered can beside the toilet for toilet paper, but only used for urine. I found the toilet filled up really quickly the TP when into the compost bag and bucket. When the toilet paper bucket is full, right now it goes into the garbage bin (in a composting bag).
    Herein lies my question…
    So I now live in the country in a small cottage (so, im heaven!) and have my own well.
    I want to build a compost bin for the solid waste in the toilet and the toilet paper that isn’t put into the toilet. Where can I put the compost bin? I read somewhere tjat it needs to be 100 ft from the well? I don’t have 100 ft on my property and I think the person who owns the scrubland behind it would not be pleased it he came back one day to find a humanour compost site on his property!
    Any suggestions? If I construct a couple bins from large plastic barrels, putting lots of holes in them except for the bottoms, would that work? My fear is contaminating my well from not quite ‘cured’ not quite composted poo….
    Thanks for reading my long long note, and I hope you have an answer to my question! I’d prefer not to stick the compost bags into the black/garbage bin as someone would with diapers or adult Depends….
    Cheers from east coast Canada!


    • Hi Heather. Great to hear from you.

      I don’t think that it would be right for me to give you a definitive answer as I don’t want to be liable, but I’m happy to give my opinion.

      I think that there are two main factors to consider:

      1. Risk of leaking – as you have suggested, this can be minimised by using plastic compost containers. Depending on the design, there could be some chance that something could leak out, so I would position these plastic bins inside some sort sealed area so that you have a second layer of protection. This could be a metal or plastic trough, or simply an area with raised edges and lined with plastic sheeting (so long as it isn’t easy for the plastic to get punctured). This will mean that if anything escapes the compost bin, it won’t actually enter the soil or groundwater.

      2. Pathogen content – regardless of whether or not anything leaks into the ground, the health risk is going to be largely related to whether the compost contains dangerous pathogens in the first place. This in turn is almost entirely dependent on what you eat and drink, after all, what goes in, comes out! hehe. Digested plants are in most cases fairly inert and so minimising or eliminating animal products in the diet of anyone using the toilet will keep pathogen risk to a minimum. Related to this, humans are also animals so if someone using the toilet has an illness that could be transmitted via their poo then that could also be a risk. However, as this is a private loo you would know at any point in time whether that is potentially an issue. There may be other factors that can affect this so that might be worth researching.

      In my opinion, if you manage these two factors well then I don’t think there should really be anything to worry about. I hope that helps!

      Tom Greenwood

  21. Thanks for sharing your experience in using the composting toilet. It’s really a good option for a green and off-grid toilet. However, as I read in some reviews, I found that it’s kinda expensive, do you have any suggestion for a cheaper option?


    • Hi James

      Yes it is expensive and found that most composting toilets are even more expensive, so sadly I don’t have any recommendations for cheaper ones other than the Separett Weekender, which is a similar product but smaller (and needs emptying more often). To be honest the technology is really basic so I think the best way to save money would be to just build one instead of purchasing a composting toilet ready made.

      Tom Greenwood

  22. Any ideas on how to compost the black waste in the bucket supplied with the separett villa. What I’m looking for is to compost the waste
    in the bucket to the extent that is safe to add to a vermiculture digester. I don’t want to add it to an external compost heap but am fine with adding some composting material to kick off the process. If there is a feasible way to do this any idea how long it needs to sit to be free of pathgens.

    Evans Mott

    • Hi Evans. Unfortunately I really don’t know the answer to this question. What I can tell you from personal experience is that when we tried leaving one full bucket of human waste with the lid on as recommended when we bought it, after 6 months it had not really changed at all. So now we just throw it in the larger compost bin. The only way that I can think of to get rid of it quickly is to burn it. Separett also manufacture an incinerating toilet and also a stove for burning the waste outdoors. I don’t know that the practical implications of that would be and I think both products are expensive, but I guess it might be worth exploring as an option.

      I just watched the video on your website. I am so inspired by what you have done inside your shipping container. Really incredible. I’m going to borrow some ideas for a project that we are working on.

      Tom Greenwood

  23. Hi there! After doing tons of research it seems that the Seperett will be a perfect addition to our guest cottage but we’re concerned about the urine pipe freezing in the winter (we live in Michigan and it drops below zero at least once a year). Have you had experience with low temperatures? Any advice to keep that from happening? Thanks very much!


    • Hi Courtney. It rarely gets cold enough here to freeze pipes so I don’t have first hand experience of any issues. I think its unlikely to freeze unless you live somewhere cold enough to freeze water as it flows. If you have a reasonable fall on he pipe then the urine will drain out of it within a few seconds, before it has a chance to freeze. You might however want to think about where the urine is going to. If it feeds into a tank outside then I guess you might need to protect that from freezing. I hope that helps.

      Tom Greenwood

  24. Thanks for all of the great comments! We are seriously thinking about purchasing this product, but before we do, my husband has a question! What about the “Dangly Bits” Is the drop deep enough so that the “twins” don’t risk coming into contact with any surfaces? And is the penis in any danger of touching the urine separator when taking a bowel movement? Thanks for answering.

    Sandy & Steve

    • Hi Sandy and Steve. Thanks for the hilarious comment. I am not aware of anyone ever having an issue with this because the separator divider is far enough back to not be a problem, but of course I can’t give specific advice for Steve. Only the two of you know the true dangliness of his bits. 😉

      Tom Greenwood

  25. Just wanted to thank you for sharing so much information about the user experience of the Separett, and for replying to everyone’s questions — because many of the questions are definitely widely wondered! I couldn’t believe that your original post was from 2012 but yet when I read all the way down to the bottom, you replied to a comment just yesterday. Just wanted to express appreciation! About to order a composting toilet for my cottage in Maine – most likely the Separett – but I totally agree about the aesthetics (and the Separett being better than most, at that.) It’s almost enough to turn me away… I have a nice antique tub and just can’t see the big plastic Villa sitting next to it. Considering the Weekender model for a sleeker profile, but it doesn’t have the handy trap door. Is it weird that I think the simplistic C-Head “BoonJon” looks better (aesthetics-wise) than these higher end models? It seems we “can’t have it all” with composting toilets just yet, but hopefully designs will come around… Thanks!


    • Hey Janine. Really nice to hear your positive feedback. 🙂

      I really don’t know why composting toilets are so ugly. I’m sure that there would be a market for one that looked good, after all people spend a lot of money to make their bathrooms look nice. I have been thinking about deconstructing the Separett and building a new casing with the same components on the inside, but its still far down on my list of things to do. hehe. I guess the BoonJon would probably be easier to dress up by virtue of its simplicity.

      Tom Greenwood

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