compost toilet or regular toilet?

Hi all,

I live in an 100 year old house and we try to keep it in authentic state and use natural materials like loam / clay / earth, wood, as much as possible.

At the ground floor we have 2 toilets. Upstairs we don't have any toilet or bathroom - it's a big space with lots of wood.

Personally I would like to keep the second floor like it is now, but my girlfriend want a toilet. So she contacted a company to do this job and they suggested to replace 1 toilet at the first floor for a new hanging toilet, so a toilet drain tube can be connected to a second one on the second floor. We have a wooden floor on the second floor.

Maybe I'm a bit inflexible and hesitant to changes - but I like to keep thinks like they used to be. So I'm wondeirng if I like plasic drain pipes in the wall - I can hide them by integrating them in the insulation, but I'm not sure if the drain pipe on the first floor needs to have some horizontal sloping, which leads to a raised floor maybe. Maybe I'm too afraid, but it just sounds complicated to me.

So then I came up with the idea of replacing the toilet on the first floor for a compost toilet (and keep the second regular toilet one on the first floor), and install a second compost toilet on the second floor.

But my girlfriend has doubts about smelly compost toilet when used indoors: she asked some friends about their personal experience and they told her that it is smelly.

The first toilet place is on the cooler north side of the house, so only in summer it gets about 22 degrees C at max. But the second floor gets very hot during the summer as this is an uninsulated roof: it gets about 35 degrees C in summer time.

I'm wondering if an indoor compost toilet can be without foul odors? If so, is this only possible with lower temperatures? Any ideas / advice?

I can let the company install two regular toilets, but this feels a bit like an environmental unfriendly action and also I don't like new shiny objects - a DIY timber compost toilets sounds much better from an esthetical point of view.  But how about odor? Will this really be a problem? I hope you guys have some advice!

Jon, what a conundrum you have got yourself, to believe your girl friends or believe people that know.
Tough call!
- compost toilets have exhaust fans that deal with odours
- plastic pipes can be painted to represent old cast iron
- roof can be insulated 35C is too hot to habitate
-

If you want a composting toilet not to smell you need ventilation.  Which is going to require running vent pipes through your roof or exterior wall.

What type of composting toilet did you have in mind?   A factory made one or something like a wooden box containing a bucket of sawdust and a toilet seat?

I can tell you from personal experience a factory made one can be disgusting, and a homemade one can smell less than a flush toilet if done correctly.

Hm! Interesting problem.

Personally, I think a composting toilet on the second floor would be a nuisance to maintain. And women have extra sensitive olfactory systems.

May I ask -- why the second floor bathroom? Is it just a place to urinate in the night? Is a full toilet -- for all bodily functions -- required?

I wonder if you could arrange (as an experiment) a high-tech, earth friendly commode -- for liquid functions. Fill with raw, dry biochar (which kills all smell) and have a skinny drain tube that overflows to an outdoor location. This is a resource!

If what is needed on second floor is really just for nighttime convenience, an old fashioned “chamber pot” might serve better than a composting toilet.

There is an option to box any pipe going out through the wall with recycled timber of the appropriate vintage.   The jointing can be matched to the rest of the house joinery so it will be sympathetic.  We have a composting toilet in our bus. It breaks down the solids and we can add the waste to the garden.. It has no smell but is vented.  Before you go ahead with anything, is there sufficient water pressure to get up to the second story?  It will not be a good evening if water is being humped up stairs.

Mk Neal wrote:If what is needed on second floor is really just for nighttime convenience, an old fashioned “chamber pot” might serve better than a composting toilet.

Very true! Though urine itself degrades quickly into a great stink (bacterial action). But if you fill a chamber pot halfway with dry biochar, the high pH shuts down the bacteria and the nutrients are absorbed for later use in soil building. Win!

John Bos wrote:I'm wondering if an indoor compost toilet can be without foul odors? If so, is this only possible with lower temperatures? Any ideas / advice?

John, I would agree that with enough of the right kind of cover material a compost toilet does not stink, assuming you're talking about the simple Joe Jenkins 5 gallon bucket method.  It can be used on the second story without modifying the house, assuming you can carry the buckets and have a plan for where and how you'll compost it.  Do your local regulations have any constraints?

Given the age of the home, are you on a septic, and do you know if it is still operating safely?  There are many types of ecological options, including flush designs, including commercial and DIY, that may be worth looking into depending on your goals, local regulations, and your preferences.  Any additional insights might help us help you better.

Hi, first of all, thanks for all your responses! I will add some photos soon of the situation.

@John C Daley: I can hide the drain pipe in the 8 - 12 cm thick insulation (cork). Yes we want to insulate our roof, but are currently busy insulating the first floor, our roof is huge, the second floor area is about 150 square meters...

@J Hillman: will an open window suffice instead of active (powered) venting? We mounted a small window in the outer wall of the toilet room. I would like to build a compost toilet myself using natural materials as much as possible like wood; I do woodworking as a hobby; So your last mentioned option, a wooden box containing a bucket of sawdust and a toilet seat sounds esthetically good to me

@Douglas Alpenstock: I agree it sounds more prone to problems having a compost toilet on the second floor, although I have zero experience. But at least it will take some exercise to get the bucket downstairs, althouht I'm used to do physical work; I'm healthy and 42 years old so I hope to be able to do some physical work the coming years

@Mk Neal: thanks for this alternative!

@Paul Fookes: yes water pressure is already facilitated on the second floor, our gas central heating boiler / wall heating divider infrastructure are mounted on the second floor so we have water there

@Douglas Alpenstock: how about the environmental impact of biochar compared to a conventional toilet? I'f I'm correct, heat (energy) is used to produce the biochar

@Burton Sparks: I will figure out the simple Joe Selkings 5 gallon bucket method. I will check the local regulations but I think it should be possible when done correctly. Yes we are on a septic, but is only functions as a connection to the sewer system

John Bos wrote:
@J Hillman: will an open window suffice instead of active (powered) venting? We mounted a small window in the outer wall of the toilet room. I would like to build a compost toilet myself using natural materials as much as possible like wood; I do woodworking as a hobby; So your last mentioned option, a wooden box containing a bucket of sawdust and a toilet seat sounds esthetically good to me

Not really, you want to create a negative pressure area inside of the toilet box so all the smells stay inside.

John Bos wrote:
@Douglas Alpenstock: I agree it sounds more prone to problems having a compost toilet on the second floor, although I have zero experience. But at least it will take some exercise to get the bucket downstairs, althouht I'm used to do physical work; I'm healthy and 42 years old so I hope to be able to do some physical work the coming years

Bucket weight is not as much of an issue if you use a urine diverter and also reduces smell. However, that would require putting plumbing in the wall or transporting the urine collection vessel downstairs as well.

John Bos wrote:@Douglas Alpenstock: how about the environmental impact of biochar compared to a conventional toilet? I'f I'm correct, heat (energy) is used to produce the biochar

Yes, but the energy comes from the wood itself as it burns. No external energy inputs are required. And once saturated with urine, the char is a valuable soil additive.

Did she say why? If it's for nighttime use, have you mulled around moving the bedroom to the ground floor?

John Bos wrote:

@J Hillman: will an open window suffice instead of active (powered) venting? We mounted a small window in the outer wall of the toilet room. I would like to build a compost toilet myself using natural materials as much as possible like wood; I do woodworking as a hobby; So your last mentioned option, a wooden box containing a bucket of sawdust and a toilet seat sounds esthetically good to me

If you have everything perfect no venting at all is required.  But I doubt you can have everything perfect 100% of the time.

The vent should be in the box,  That way air gets sucked from the room, into the box, and out the vent.  In my case the house is almost always warmer than outside so the vent works without a fan.  Although having a fan for while you are actually using the toilet isn't a bad idea.

With a vent connected to the box the smells never make it out of the box.  Compared to a normal bathroom vent in a ceiling the air doesn't doesn't get removed until smells have come out of the toilet and mixed with the air in the room.

If you use sawdust as your cover material the moisture of it makes a huge difference in how the toilet works.  I find dry sawdust doesn't work at all.  It is much better to use damp sawdust,  It should feel kind of like a sponge you squeezed out as much water as you can from.



Do you plan to have any provision for hand washing?

What do you plan to do with  the contents of the bucket?  

Hi John,
You have many excellent answers for dealing with the composting toilet situation. (On a side note, I will throw out that a whole bunch of "normal" toilets can smell too, haha).

I'm actually going to make an argument for the "normal" toilet option. First... if your girlfriend is asking for that option, and is hesitant about a compost toilet, I would give her a normal toilet. I would maybe add a composting toilet in an out building and ask her to try it once in a while to get her used to it. You don't want her getting a bad experience and turning against any other eco-friendly things you may want to do down the road. Perhaps a compromise here will help down the road. Many people are not ready to jump in head first. They want to stick their toe in and see how cold the water is first.

Composting toilets are great, and I only have limited experience with them, but I don't think "normal" toilets are as bad as some people think. Once you get everything hooked up, a toilet will last a long time and doesn't need electricity to run. You can haul a bucket of water and fill up the tank, and gravity will do the rest. If the septic system is treated right and sized properly in the beginning, it does not need servicing for a long time. It breaks down the waste a bit different than a composting toilet, but it still breaks it down biologically and spreads the residue out through the leach field.

Ours is a bit different, but I also live in a 100 year old house and there was a toilet added to the second floor before we got it. They just build a box around the drain pipe coming down from the upstairs. We painted it the same color as everything else and now I don't even notice it.

Just a note that my wife is onboard with nearly every damn weird building thing I want to do but a flushable toilet is not up for compromise. She's lived with two different styles of composting toilets, lived on boats, etc. Mandatory to have flushing toilets and honestly she's right (for our family).

Hi, thanks again for the new responses!

I think I will add a second regular toilet on the first floor - and connect it to another regular one on the second floor, as my girlfriend has some doubs about composting toilets and fumes. I will then build a compost toilet outdoors using wood... This will be a compromise, but we still can gather experience by using the outdoor composting toilet. The only drawback would be during winter time or when it's rainign - but this is a luxury problem

John Bos wrote:Hi all,

Maybe I'm a bit inflexible and hesitant to changes - but I like to keep thinks like they used to be. So I'm wondeirng if I like plasic drain pipes in the wall - I can hide them by integrating them in the insulation, but I'm not sure if the drain pipe on the first floor needs to have some horizontal sloping, which leads to a raised floor maybe. Maybe I'm too afraid, but it just sounds complicated to me.

So then I came up with the idea of replacing the toilet on the first floor for a compost toilet (and keep the second regular toilet one on the first floor), and install a second compost toilet on the second floor.

But my girlfriend has doubts about smelly compost toilet when used indoors: she asked some friends about their personal experience and they told her that it is smelly.


I'm wondering if an indoor compost toilet can be without foul odors? If so, is this only possible with lower temperatures? Any ideas / advice?

I can let the company install two regular toilets, but this feels a bit like an environmental unfriendly action and also I don't like new shiny objects - a DIY timber compost toilets sounds much better from an esthetical point of view.  But how about odor? Will this really be a problem? I hope you guys have some advice!

A quality waterless or composting toilet will absolutely not smell whatsoever. We have one in our city home, and prefer it to the flush toilet. The newer ones are better, especially if it's airtight with an air intake. Otherwise you will be drawing in heated air then exhausting that heated air outside. We've used several, and the Thinktank waterless toilet is the best so far.

Douglas Alpenstock wrote:Hm! Interesting problem.

Personally, I think a composting toilet on the second floor would be a nuisance to maintain. And women have extra sensitive olfactory systems.

May I ask -- why the second floor bathroom? Is it just a place to urinate in the night? Is a full toilet -- for all bodily functions -- required?

I wonder if you could arrange (as an experiment) a high-tech, earth friendly commode -- for liquid functions. Fill with raw, dry biochar (which kills all smell) and have a skinny drain tube that overflows to an outdoor location. This is a resource!

Wow, amen on "And women have extra sensitive olfactory systems.". My wife has asked me, at least 1x a day, does this smell funny?

It has been several months now so I wonder if the OP found a satisfactory solution?

I hope he will reply with that solution.