How to compost urine using a straw bale. Dry toilets for all climates.

The Piddleposter

 

A great way to process dry toilet liquid for around 6 euros or 5 dollars worth of materials. 

Whether you're a homesteader/smallholder looking to cut your water consumption or someone who just wants not to have to take off muddy boots when needing to use the bathroom.....

 
...even though the cows may have something to say about you pinching their bedding.

Introduction

 

A few months ago I received a question regarding the practicality of using a dry toilet in a really cold climate.

My thoughts on this are as follows:

The solid waste from our two-bucket dry toilet system would still go into the composter, I would advise the use of larger amounts of straw to act as an insulator as well as furnishing the carbon necessary for the bacteria to work. Even if the temperatures are very low, as soon as Spring temperatures arrive, the composting process would speed up and I would expect after the passage of two years for the compost bin contents to be completely transformed. I would have said that if one already has a climate able to compost vegetable matter/ garden waste then there will be no problem with that of the toilet contents. 
 

 

The liquid waste would probably be harder to dispose. Ordinarily, our urine is diluted with grey water from the house and then poured around the garden. When the temperatures are below zero I do see a problem with the frozen ground being unable to absorb this. Fortunately for us the cold spells do not last too long and normally the soil in the more protected areas of the garden are still porous.

I realise that for people living with longer, colder Winters the liquid waste would become a burden. So, my idea is to make a composter specifically for handling “neat” urine and capable of producing a valuable compost at the end of its processing.

The straw bale composter

Human urine is 95% water the rest is a rich mixture of chemicals the largest proportion being nitrogen. To make good garden compost you need a Carbon to Nitrogen ratio of about 30:1 and so the almost total carbon content of straw makes it an ideal companion in the compost bin.

This is an idea becoming more commonly seen at outside public events as no drainage for the liquid is required. The toilet can comprise of an enclosure with a seat if needed and an appropriately placed straw bale to receive the liquid direct from source.

French designers Faltazi have come up with an easily attached folded polypropylene or stainless steel 'funnel' so as to produce an ecological pissoire. The funnels are pushed into the sides of a straw bale at the appropriate height for men. http://uritonnoir.faltazi.com/en/

My experiment was to make a suitable container for a straw bale and empty the liquid waste from its receptacle onto it every day and see what happens to the urine and the straw.

The Design.

Obviously the compost bin has to fit around a straw bale. The standard bales in Europe are now huge cylinders and are designed to be mechanically lifted and dispersed throughout the farmer's barns. 

The organic farm where we buy our grain for our birds has these same sized home-grown organic straw bales and he uses one each morning and night for the bedding of his 50 head Normandy herd. 

Even so he has other livestock areas where he only uses part-bales. If we give the farmer 24 hours notice he can take a part-bale and re-roll it to a more manageable size. This is so it will fit into the rear of our estate car/station wagon, even then it is still quite a push to manhandle it into place. For 5 euros or 6 dollars we got this bale with enough left over in the deal to keep the Hen Houses supplied for several months. So for a small initial sum you can end up with some great and truly organic compost! You will probably have an organic farmers' register for your area, so check out the dairy or other livestock farms and see what they have on offer. Mixed arable farms will also have straw and again I would always go for a certified organic farm, where you can be assured of them not using chemical sprays and/or synthetic fertilisers.

These bales when laid on their sides in fields will shed rainwater for some considerable time, a desirable feature for the farmer but not for the urine composter hence, the bale has to stand on its end to expose the more porous part of the bale uppermost when in the composter.

 










The link for the design and construction of the compost bin on the left can be found here:
Pallet wood compost bin 


If you've seen my other compost bin design you will know of my sliding wall plank system that I developed to ensure easy access for emptying and the facility to exchange rotten planks with new ones. For the new bin I opted for only the front elevation to be of the sliding plank format, the other three walls were to be pre-made in the workshop. This would still mean that the wall panels would be easy enough to carry into the garden for assembly on site.

The cylindrical straw bale has a height of 120cm. Perfect for my needs as the standard pallet plank is exactly this length.

A waterproof lid fits on top of the container to ensure weather protection.

Fabrication

The three pre-constructed walls were made by nailing pallet planks to top and bottom horizontal rails. The wooden rails of each wall were longer than the wall width. This protruding portion fitted over or under the other walls' rail, a clearance hole was drilled through the two rails and a threaded bar was inserted. Nuts on the threaded bar were tightened once the walls were in position. 
 

On the front elevation of each side wall was a vertical post running from top to bottom to which the spacer rails were screwed and onto these were screwed the retaining rails. The resultant gap between the post and the retaining rail had to be enough to allow the wall planks to pass.

One important point is that the upper rails of the side walls projected beyond the rear wall of the composter, this to provide the pivot point for the lid.

Here is the step-by-step film showing the construction:

All the best and thanks for dropping by. Feel free to comment ask for information and/or share this article.

Cheers, Andy

© Andy Colley 2014

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Home-made, Big, Low Cost Glass Greenhouse from Free Recuperated Windows Part 2

The very first step in constructing the greenhouse was to decide on the size for it. We'd earmarked a vegetable plot where it was to go and as it had a hedge along one edge and a rose border on another, both of which we wanted to retain a practical size of 5m long by 3m wide was decided. This gave adequate space for access with ladders or steps during construction.

Although it is a large sized greenhouse and in itself quite an imposing feature, it actually fits very well into its surrounding landscape. Being surrounded by greenery as it is now, obviates the need for shade cloths, which in the early days were necessary to prevent the scorching of leaves in the very hot, clear days of Summer. We live near the sea and at times the light here can be very intense.

The roof covering was to be of 200 micron polythene UV stabilised (polytunnel material) and this could be purchased by the metre and was 7.5 metres wide. As the roof was to be gabled we bought a 4m length, the polythene width was more than enough to cover the greenhouse length.

For the south 3m wide end I had recuperated some French windows and these and the entrance door on the North end set the wall height of the greenhouse.

Having now decided the overall dimensions of the greenhouse the preparatory work could begin.

All of the windows I'd collected were casement windows, that is, windows that open on hinges attached to one vertical side of the frame. Most of them were paired and had a weather strip where the two windows met in the middle.

Along the bottom edge of all these windows was a weatherboard to deflect rain running off the window onto the window sill. As the casement window fits into a frame this moulding is not flush with the bottom but is attached about 10-20mm from the bottom edge.

Apropos of hinges

The hinges need to be removed as they will interfere with the fit.

Some hinges can be removed by unscrewing but, bearing in mind that these are old windows, the screw heads will usually be sealed under several coats of paint. Nevertheless, with a little care they will usually come out. I clean the paint away from around the screw heads with a sharp awl and ensure the screw heads have all the paint removed so that the screwdriver fits tightly. If after all this effort the screws refuse to budge then you have to resort to drilling out the heads, it won't matter if the rest of the screw remains in the frame. Alternatively, you can use a hacksaw or angle grinder to remove any protruding part of the hinge and leave the remaining metal plate complete with screws in place.

.

To bring the windows' heights to that of the French windows I decided to support them on walls made from pallet wood. Now that I knew the wall lengths I could sort the windows to fit, number them and mark their position on a plan.

Before making the walls, the bottom of each window projecting beyond the weatherboard was sawn off providing a wider face to rest on the wall.

TIP: (photo above) Screw a plank of the appropriate thickness to the face of the window so as to ensure that the saw blade will cut a square face to the bottom of the window. 

The wall panels were made from pallet wood planks nailed to a rectangular frame. Each frame was again of pallet wood but I selected planks for this from more robust pallets (approx 100mm x 22mm, 4" x 1"). These planks were screwed together to form the frames and the pallet wood planks were nailed to what was to become the outside face thus forming a box.

There were seven 75mm (3") square wooden posts, each bolted to a galvanised steel stake driven into the ground (one at each corner, one midway along the longest sides and one to form the doorway). A line running from post to post marked the perimeter to which the wall panels needed to abut.









In addition, I made T (Tee) shaped stakes from 22mm thick pallet wood, which were to be driven into the ground on the inside of the greenhouse. These would provide a solid support for the wall panels.

All the above preparation meant that when we finally came to construct the greenhouse it went together as a kit.

The roof trusses too we pre-fabricated in the workshop too but for clarity I'll deal with these in a separate post
.

If you are thinking of building a glass greenhouse and would like to know of some of the extra plants, in particular tropical spices you will be able to grow, then sit back and take a look at this film:

Thanks for dropping by and please feel free to share this article, comment, ask questions and if you'd like to be assured of getting the next post, then sign up to follow this blog.

All the best, Andy

© Andy Colley 2014

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Make a Wooden Fuelless Cooker or Hay-box - No Power? No Worries. Hot Food.

The cardboard box version of the fuelless cooker as described in my post a few days ago is fine as a 'quick fix' or an emergency back-up. In this post I'll share how to make a more robust model which you can keep to hand in the kitchen or, as we show in the film, to take in a car to provide hot, nourishing food on a journey. There are two ways you can use a fuelless cooker, firstly you can use it to cook a whole meal, this was the way it was used in previous centuries both for men and women working in the fields and long distance travellers and how we used it in the film. Secondly you can use it in your kitchen, to save energy when cooking a stew or similar dish, which requires slow cooking. We actually did this too with our cassoulet when we returned home in the evening, taking it from the box, where it was still quite warm and transferring it to our wood cooker. I have to tell you that after several years of making and eating this dish it was the best we had ever eaten! Furthermore we had saved on four hours of fuel.

Design and Materials

Our wooden box sits next to the telephone and is robust enough to act as a comfortable low seat. It was made using pallet wood and 10mm (3/8") thick pine cladding. This latter was left over from when I made the hen house last year. The insulation was 45mm (1¾") thick organic hemp and vegetable fibre, purchased in a 1250mm x 600mm (4' x 2') sheet for about $5.00.

I based the design of the box around our largest saucepan and for ease of loading when hot, the lower portion of the box was not much higher than the two handles on the side of the pan (as seen above). The box lid was deep enough to fit over the portion of the pan standing above the box rim.

Both the base and the lid were made in the same way, that is the vertical sections that made up the inner and outer walls were stapled to an upper and lower square frame, the width of the frame was the thickness of the insulation. 

I arrived at the box dimensions from the size of the saucepan. This size would be the minimum internal dimension of the box. To arrive at the outside wall height for the box base I had to add the thickness of the box bottom, the insulation and the thickness of the platform wood. I always tend to regularly check the measurements especially prior to cutting the wall material - better to be safe than sorry!

I had originally thought of making the frames like picture frames, with mitred corners but decided against it for two reasons, one is I'm pretty crap at achieving consistently accurate cuts, especially at 45° and secondly and more importantly I didn't believe that sort of joint would be strong enough to cope with the load from a pan full of hot stew! 

Construction

 


Select the pallet wood for the frames, cut to width (that of the insulation thickness) plane it smooth and cut to length.

Four frames are needed (2 for the base and 2 for the lid). To ensure they are all exactly the same size assembled them in a jig. I made this by screwing three straight pieces of wood in a 'U' shape to a piece of chipboard. The size of the U being the size of the frame and the corners at right angles. 
    

Position the two vertical legs of the 'U' against the sides of the jig and check that they touch the bottom jig edge, apply wood glue (PVA) at the corners and put the third, horizontal part of the 'U' along the corresponding jig edge. Ensure that all 3 pieces are pushed firmly against their guides and staple or nail where they overlap. Turn the, now joined three wood pieces around in the jig so that the fourth, open side of the 'U' is sitting against the bottom jig edge. Once again glue the corners and position the fourth piece of the frame on top and staple or nail.
 
The reason I used a 'U' shaped jig and not a complete square is that it is much easier to remove the frame by sliding it out rather than trying to lift it.
Repeat for the other three frames and then stack all four frames and clamp at each corner and leave to dry.

The bottom face of the box has pallet wood planks nailed to the frame to form a solid support.

Turn the base over and cut and fit two extra pieces of wood to the frame. This is to furnish a vertical face to which the box walls can be attached.

The saucepan is to sit on an insulated platform made to fit into the square recess created in the previous stage. The platform is about 20mm smaller than this recess to account for the wall thickness and is deep enough to fit a square of the 45mm thick insulation beneath it. Being removable it can be taken out and cleaned if there is any spillage.

 

Now comes the clever bit, I already know the height I need for the box base so I measure the internal wall height and include the height of the insulated base. Cut the 10mm cladding to this length.

Use panel pins to attach the walls to the base. Ensure a good fit at the corners.

The base now looks like this. 

Prior to fitting the top frame to the base, attach two additional wooden pieces, so as to make a flat surface to the frames upper face.

Nail, or staple the top frame to the walls of the base.

The box now looks like this. The outside walls can be cut to length and the insulation cut to size for the walls and the insulated platform.

 

The insulation should be a good, close fit to ensure maximum efficiency.

Attach the outer cladding. I tend to use the stapler because it's less tedious but panel pins are fine.

Cut two carrying handles and fix to the box, screwed through the walls into the upper frame.

The insulated platform can then be dropped into the completed base.

The construction of the lid is similar to that of the base except that the top outer cover of the lid is put on last. I found that this makes it easier to attach the inside walls to the frames.

 

First, cut the interior walls to length, which is the height of the pan  and lid projecting above the box base plus the insulation thickness and the thickness of the cladding covering the insulation.

Fix the interior walls to the lower frame........

............and the upper.

To make the space for the insulation at the top of the lid cut two 45mm wide pieces of wood to the internal dimension of the lid and wedge them in place at the top of the lid, with a few millimetres protruding above the uppermost face.

Cut cladding to fit to these two pieces and attach. The cladding must not overlap the edges.

Remove this assembly, turn it over and put it back into the lid top.

 

Tap it flush to the upper face of the frame..........

..........and attach to frame.

Cut insulation for walls and

top, cut cladding and attach.

Cut and attach two handles, securing them, as before, by screwing them to the upper frame.

 

To ensure a snug fit of lid to base, cut four pieces of fruit crate wood (5mm pine), to fit around the inside of the lid perimeter and chamfer one edge of each piece.

Staple, or nail these pieces to the inside wall of the lid, chamfer facing out and protruding about 10mm. This acts as a guide to align the lid to the base and produces a more effective seal to prevent heat escaping.

And there it is all ready for the next power outage, energy price hike or picnic.

Bon appétit! Now if you'd like to sit back and watch the film: 

If you would like a cheap and cheerful project, which is great fun to make and use, then take a look at my cardboard box fuelless cooker design


Thanks for dropping by and please feel free to share this article, comment, ask questions and if you'd like to be assured of getting the next post, then sign up to follow this blog.

All the best, Andy

© Andy Colley 2014

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