Bins, bays or Windrows
Small village sized schemes almost invariably want to contain their compost in bins. It helps keep the site tidy and well managed. Larger schemes turning compost mechanically either use very solid bays or make compost in windrows which are simply piles which extend laterally and can be turned by the side or in very large systems by special machines which straddle the whole windrow.
Bins
Most bins, that community groups use, are made from wood. The most expensive used is pressure treated sawn timber (tanalised). The advantages are that the wood will last longer and you can make the fronts (and backs and internal divisions) out of planks which slide in and out of slots. This makes the compost easily accessible for turning. However it is the most expensive option and many people don't like to use tanalised timber or timber treated with other toxins, especially when it's for compost.
Sawmills sell 'outshelves'. These are the first cut from the trunk, complete with bark and taper from a thick base away to nothing. They will sometimes let you pick through a large pile cutting off both the thickest and the thinnest ends with a small chainsaw. Cutting the wood into the right number of lengths that you need will save on waste. You will also need solid 4 inch square posts for your framework. Instead of having slotted removable fronts you can make lighter weight front sections, like a gate which is lifted on and off and tied up to the main frame. The inevitable gaps are covered up with flattened out cardboard boxes, this also helps to prolong the life of the timber.
Some people advocate providing extra ventilation by putting a piece of heavy duty mesh on concrete blocks at the bottom of the bins. This is quite a costly operation and has the disadvantage of not allowing earthworms to migrate into the heaps. It is only useful if you are composting very dense wet materials. Ventilation should not be a problem as community projects are usually processing large amounts of woody materials which provide more than adequate drainage and aeration. Usually it is a good idea to tread down your heaps as you go and add lots of water otherwise you will get have dry pockets where no composting has taken place.
Bins can also be made of ; old doors, railway sleepers, pallets, fencing panels, all manner of scrap wood and even bricks or blocks.
Pallets can be obtained for nothing and anyone can line them with cardboard. Use a staple gun, you can even add a layer of opened out plastic sack to help keep the moisture in. Then all you have to do is tie four together - instant compost bin!
In Skegness they have two large containers built out of concrete blockwork joined onto the back of a greenhouse. These are filled with woodchip and watered and the heat piped into the greenhouse! Straw and hay bales produce excellent superinsulating compost heaps and take a surprisingly long time to decompose themselves.
Even corrugated iron or wire mesh on its own can be used to make a heap but will provide no insulation and wire alone will provide too much ventilation, fine for leafmould not so good for compost. (You can of course line these containers with carpet, cardboard or paper and have a very cheap bin.)
Signs
As well as places to compost in you need designated areas for stockpiling materials. Woody materials need to be carefully stacked awaiting shredding, finished compost needs to dry out before sieving.
A separate bay is needed for woodchip and so on.
If your site has public access then you must have very clear signs saying what can and can't be left for composting; what types of materials to put where e.g. "Woody materials here" "Soft sappy materials here". (Grass cuttings fresh green weeds). "Earthy stuff (and weeds with lots of earth on), please leave in the bags" "Unsure/mixture" "Leave In bags".
Unfortunately lots of people don't read signs and just want to dump and run so it's important to maintain your profile with articles in local, papers and bulletins and displays at events etc. Sites with public access must be checked very regularly, preferably daily so that any soft green materials can be layered into the heaps with some tougher "soak" materials which you can keep in a heap or sacks nearby.
Small amounts from the sacks of earthy materials can be added at the same time.
