Kiwi Bog Detail


Careful if clicking on thumbnails as they are quite high resolution                               see the solar system


All users must be seated.

used Toilet paper must be dropped into the faeces bucket not placed in the urine path.



The bog is what is known as a urine separating toilet. It separates faeces and urine just below the seat. Urine is captured by a tray and piped to your waste system through a connection below the bog front. The way urine is disposed of depends on your application. See the separate sections; buildings ,sea, and  land mobile

Faeces and used toilet paper are accumulated in a plastic bag which lines a large bucket. This bucket will last one person for two months or more. A low power fan removes air through the flue and toilet roof to outside. Outside any odor rises and is undetectable. Fan noise is usually inaudible outside of the toilet. The fan starts dehydration of faeces.


The photo to right show the bog top from below the tray. More recent versions do away with the piping and a stalk rises from the base to receive the urine. This allows the flue fan to clear away any urine smell as there is an air gap between the tray and the funnel on top of the stalk. It has the major bonus that the top can be removed completely for cleaning and bag changing.



It is very important that protective gloves are worn at all times when in contact with the inside of your Kiwi Bog. Gloves should be of the long sleeve type so that no skin can contact any internal surface.


Also see treating outputs.htm. Once the bucket is full fold the top of your bog forward to reveal the bucket inside. Tie the bag and put on the bucket lid before removing it to a place suitable for three to six months storage. Temperature is the prime determinate of time required to make faeces suitable for return to the soil. Faecal coliforms will die off in less than 50 days at 20 to 30oc but in up to 150 days at 10 to 15oc. These figures come from the WHO.

Once you have your bucket on site add about half a cup of water and sufficient soil to cover the top inside of the bag. Fit the lid loosely so that the bag can breathe while the composting process completes. Another bucket can be placed in the bog with a new plastic bag fitted over its rim. Please note that only one bucket and lid of each size are supplied. Further buckets are readily available from plastic shops.


The bog uses a low power fan to move air out of the bog and up the flue. The picture to right shows the fan with cover removed. Four screws give access to the fan and replacement only requires reconnecting two wires. There is a fuse to the right of the fan case which can be replaced without removing the fan cover. The fan is mounted in foam rubber to isolate its vibration from the bog case. Replacement fans are less than $40 incl. GST.


The bog bucket should be cleaned after each bucket change. Access to the inside of your bog is easy and all surfaces can be cleaned with the cleaner supplied which has been specially prepared for your bog plastic. Only use cleaners designated safe for acrylics as damage is likely and your warranty will be voided.  Cleaning is the main factor influencing the life of your bog. The better condition you keep it in the longer it will last.


Bogs are often available from stock.


Bogs should be stored with the bucket empty or the faeces bag sealed and the fan off. They should be kept out of direct sunlight.


See our new page that shows the manufacturing check list used when preparing each bog. This shows exactly what is supplied with each bog.

Before installing your bog you need to be assured that it is assembled correctly, particularly the flexible urine tube connections to the urine separating tray and to the outlet connection inside the base of the bog. All connections in the urine path are tapered. The top of the flexible urine tube is a tight push fit onto the tapered outlet of the urine tray. The bottom connects to a tapered part that in turns fits in the tapered outlet socket. If you have any concerns about this connection you may wish to glue it in place using 'Marley MCS white uPVC solvent welding cement'. The reason not to glue is for later cleaning and clearing of the urine tube. Because the components just twist apart it makes it easy to clean or remove any foreign objects.

When ordering your bog you can choose to have the urine pipe exit from the rear of the bog instead of the more usual front base exit. This could deal with situations where you can't get under floor access for any reason.

A simple passive vent is supplied that fits on top of the flue pipe which can protrude from your roof by as much as you wish although you will need to consider the effect of wind it it protrudes very much. A rubber roof cowling is supplied to seal the flue on the outside of the roof and a plastic flange is supplied for the inside ceiling. A rotating vent is available as an alternative to this simple vent as extra but only suits relatively flat roofs. It costs around $80incl GST.

Inside your toilet, position the flue pipe into the hole in the ceiling until it abuts the spindle. Cut it carefully to length so that it is a tight fit to the 65mm receptor fitting on the back of your bog.

Installation of the passive vent is simpler as the flue pipe can protrude some distance above the roof and the passive vent just fits on as a cap. Please note that we don't supply anything for the roof side of the pipe protruding. You need to purchase a suitable rubber roof vent pipe flashing from a plumbing supplies.

It is possible to pipe your flue out behind your bog. You need to consider that the odor rises from the flue outlet so it needs to be as high as possible. It also needs to be protected from insects and rain entering the flue.

The flue should be supported up the rear wall with the brackets supplied and the washer placed against the ceiling and held there with sealant.

A short length of urine pipe is supplied with a right angle bend with your bog. The urine tube must be connected to the outlet on the bog. If the outlet is below the bog then sufficient space needs to be allowed for both the pipe and its coupling to the bog wall. The bog pipe is 34mm and the coupling is 50mm.

The bog should finally be bolted to the toilet floor using the stainless self taping screws and washers supplied as near to the base edges as practical and all joints sealed. Additional protection can be afforded by spraying the interior of your bog with a protective silicon film. When cleaning check for any signs of rust around the fixing screws in your bog base and replace the screws immediately if any is encountered otherwise serious chemical damage to the bog plastic will result.

Note: If your urine pipe comes out directly below the urine separation tray: it is intended that the pipe never disconnect except for cleaning or clearing in exceptional circumstances. To gain access to your faeces bucket; tilt the top forward sufficiently to remove the bucket but not so far as to disconnect the urine pipe. You will find that the urine pipe will hold the top in position while you work on the bucket. To reconnect the urine pipe; place the top in front of but almost touching the base tilted forward enough to place an arm between the two. It is important that the lowest part of the top be below (and outside) the rim of the base.  In that position you will find that you can connect the urine hose.  Better to leave the bucket out while you reconnect the urine hose.  Make sure that the two connections twist tightly together at both ends


The Bog has been manufactured to comply with New Zealand and Australia standard AS/NZS 1546.2:2001 which is a joint standard for waterless composting toilets. A 12volt power supply is required capable of supplying 1 watt continuously or a solar installation running on less than 1 watt can be provided. Usual bucket capacity is 20lts.

The bog without flue is 510mm to the top of the seat. 610mm from front to back at seat height and 445mm from side to side at seat height and 400mm round at floor level. Bog weight is less than 15kg empty.

The bog is manufactured from 7mm ABS plastic. It utilizes a high quality seat manufactured in New Zealand by Dux Industries.

Specifications may change at any time without notice.