Showing posts with label making seats for a dry toilet. Show all posts
Showing posts with label making seats for a dry toilet. Show all posts

Make your own dry toilet Part 3 The Seats continued

Welcome to the continuation of this project on making the dry toilet seats. If you have just landed on this page, then the first part can be found here.

DIY pallet wood dry toilet work in progress

For the seat itself I had selected some wood planking 140mm x 30mm (5½” x 1¼”) that I had intercepted before being thrown into a skip. Already planed smooth this was ideal. On  the very first seat I made (still in use) I used 20mm (¾”) pallet wood and this was okay except it did take some effort to plane it to an acceptable smooth and splinter-free finish.

make your own dry toilet from pallet wood
The planks were sawn to length and laid onto the top of the frame. Previously I had marked the centre of the frame with a pencil line and I laid the seat planks for both sides to this line. The seat supports remained clamped to the side frames and hence once in place a line could be drawn on the underside of the seat indicating the supports positions (image at start of article).

diy dry toilet from pallet wood work in progress

Each plank in turn could then be removed, turned over and drilled.

make your own pallet wood toilet seat

Prior to screwing I'd countersunk the screw holes on the top face of the seat planks and then ran a bead of PVA wood glue on the upper faces of the supports. I also ensured that the front edge of the seat projected about 20mm (¾”) over the front edge of the frame.

The shape for the hole in the seat I obtained simply by tracing the outline from an existing toilet seat onto a piece of cardboard. Once cut out, this became the template for the hole and could be traced around in the correct position on the seat planking.

making your own pallet wood dry toilet

When the glue bonding the seat planks to the supports had dried, the holes could be cut using a jigsaw. The buckets were put in place and the alignment was checked. As an additional support for the seat planks I glued and nailed laths of wood on the underside of the seat that were narrow enough not to impinge on the bucket rim.

making a pallet wood toilet seat

The upper edge of the hole was rounded, for user comfort and although it could be done with a rasp and sandpaper, I found it much quicker using a router fitted with a roundover bit.

  making a pallet wood toilet seat lid - hinges

To make the lid I cut 20mm (¾”) pallet planks to length and laid them on top of the seat, the plank at the back flush with the rear edge of the seat. The lid pivoted on the same dowels as the seat thus four ‘L’-shaped support arms were cut.

The shorter arm of the ‘L’ was long enough so as to be able to be drilled for the dowel to pass through. The long arm was laid onto the lid planks and the pivot hole in each one was drilled.

making hinges for DIY pallet wood dry toilet

To make this operation easier, each arm was held against the inside face of one of the outermost seat supports and the hole was drilled using the previously-drilled holes in the frame and support as the guide. During drilling I used a piece of wood to wedge the arm firmly in place.

NOTE: Because I had drilled and checked the hole alignment in the support frames I knew that the pivot holes were in the same position thus, all of the holes in these arms were drilled through the same guide holes.

finishing the frame of diy pallet wood dry toilet

Prior to fitting the lid, I nailed planking to the front face of the seat frame and chamfered and smoothed the top edge with a rasp and sandpaper.

With the lid planks in position,  each pair of arms were fitted onto their respective dowel and lowered into place. The arms were drilled and screwed to the lid planks.

 Making your own dry toilet systemNow all that was needed was to put the seat in place in the toilet cabin and this is where the design for the cabin works really well.
As the wall planks are not fixed in place, they can be slid out from their retaining bars until there is enough of a gap for the seat to pass through. This means that the seat can be fitted into a cabin not much wider than itself (about 50mm (2”)).

finished homemade dry toilet form pallets
With the buckets in place and sawdust in a separate container, the system is up and running!

.. and now if you'd like to, sit back and watch the film of the construction of the seats:

Making your own dry toilet - the seats in place
All the best and thanks for dropping by. Please feel free to share this article, comment and/or ask for further information.

Until next time!

Cheers, Andy
© Andy Colley 2015


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Make your own dry toilet Part 3 - The seats

There’s an old joke about thieves breaking into a local constabulary and stealing all their toilets. The next day it’s reported that:
“The police have nothing to go on.”
I realise how remiss I’ve been in not furnishing the details of the third, final and essential part of the dry toilet system and will correct this forthwith.

As this is quite a lengthy article, I have divided it into two. (If you are just coming to the dry toilet project for the first time, then part one of our whole set up, which includes details of the design and fabrication of the compost bin and cabin, can be found here.)

Making seats for a dry toilet with Bob the Sebright rooster
 Work in progress - Bob the Sebright aka the Guv'nor


The toilet seat is for the ‘two bucket’ system. One side is for collecting liquid and the other is for solids. Needless to say one cannot avoid some liquid in the latter bucket but it is minimal and will be absorbed by the sawdust that is added after every visit. The idea is that the solids bucket is dry enough to permit the aerobic bacteria to get to work . The liquid waste can be disposed of separately either diluted with rainwater and used directly on the garden or put into the urine composter (see related post below). The other bonus for us is that when we’re working in the garden it’s really handy having a toilet where you don’t have to worry about taking off your wellies or muddy work boots to have a pee!


The receptacles for the waste are two identical size buckets. It is the size of these buckets which determine the distance of their support shelf. from the underside of the seat. The hinged seats are made of wood and have a hinged cover over the top. It would be possible to purchase a couple of toilet seats and attach them to the base, but my intention was to make everything from re-purposed wood (except the buckets). 

DIY dry toilet making the seats

The important dimension was  the seat height and this I measured from that of a conventional toilet.


The seat carcass was made of 3 rectangular frames oriented front to rear connected by top and bottom rails. The front elevation was clad in planking. The upper face of the frames was the face against which  the seat rested. I first selected the wood I was to use for the seat.. The thickness of this wood had to be included in the dimension for the overall seat height.

Dry toilet seat work in progress

There were six legs in all and they were cut from the stringers of a two-way entry pallet. They usually have a cross-section of around 29mm x 80mm (1¼” x 3¼”).


make your own dry toilet seat framesEach pair of legs were joined with pallet planks (leg braces) 18mm x 80mm (¾” x 3¼”) at the top of the leg and at the bottom. The position of the lower leg brace had to be determined such that its upper edge would carry the horizontal planks upon which the buckets rested. So in my case, the distance from the top of the leg to the upper face of the lower leg brace was determined to be: the bucket height (260mm) plus the horizontal bucket support plank thickness (18mm) i.e. 278mm (11”).

The top edges of the upper leg braces of the frames were flush with the top of the leg. The centre leg frame had the leg braces on both faces of the legs so as to furnish support for each seat. Each frame was assembled with wood glue and screws, It was essential that the screws at the upper rear corners were not going to foul the location for the hole for the hinge dowel for the seat.

The hinges for the seat and lid were simply pivots made from wooden dowel passing through drilled holes in the upper leg braces into holes in the seat and lid supports. In the first incarnation of the seat, I made the base and then drilled the hinge holes in the frame using the fully assembled seat and hinge as the guide. I found it was very difficult to get the electric hand drill in position to drill the centre hinge hole due to the length restriction. So subsequent constructions had the hinge holes drilled in the seat and lid supports before they were assembled. This obviously meant that I had already selected the timber for the seat supports as it was in these that the other hinge holes were drilled.

The position for the dowel hole was marked on the side frame and the hole was drilled To lessen the chance of the drill wandering, I drilled a pilot hole and then ’opened up’ this hole with drill bits of increasing diameter.

DIY dry toilet checking hole alignment

To check the accuracy of the hole position, I stood the three side frames together on a flat surface with the legs aligned and pushed a piece of wooden dowel through the drilled holes.

make your own dry toilet work in progress

The frame for the base was then assembled. Front and rear rails cut from pallet planks were screwed to the outward-facing elevation of the front legs of the side frames, at the top and the bottom and the inside edge of the  rear legs of the side frames, checking that the frame remained square.

DIY dry toilet project from pallet wood

The seat supports were of the ‘stringer’ timber from a pallet cut to 28mm (11/8”) width and cut to length. For drilling the pivot hole in these, the supports were clamped against the side frame  in the correct position and the hole in the side frame became the guide for the drill bit.

In the second and final part of this project I'll describe the making of the seat top and lid and fitting the finished project into the cabin. There will also be a film of the whole process.

dry toilet at a show
All the best and thanks for dropping by. Please feel free to share this article, comment and/or ask for further information.

The continuation of this project can be found here

Until next time!

Cheers, Andy
© Andy Colley 2015