In order to stay safe on the roads, you need to make sure that your car's tyres have good, deep tread. The risks of a blowout can be catastrophic. However, this constant demand for new car tyres means that the old ones have to come off. And then what do you do with them? You can re-tread a car tyre, but even this can only be done so many times before the structural integrity of the tyres is compromised. And then you have to decide what to do with the old tyre.
At first glance, a used tyre is an environmentalist's nightmare. Even though it's made mostly from a natural and renewable resource (rubber), tyres are not very biodegradable and they'll sit for millennia in landfills taking up valuable space, and if you burn the things, they release some very nasty smoke and pollution into the air. So what do you do with them?
Well, if you take another look at an old tyre, you realise that you have something that is very rot-resistant and is fire-resistant. These things just have to be assets.
Large scale recycling companies can recycle old tyres up to a point. Sometimes, shredded car tyres can be used as part of the substrate (basecourse) in making roads, which reduces the need for quarrying stones. Unlike other waste materials that have potential for this use (e.g. slag from refineries), shredded tyres do not create toxic leachates that can be washed out of the roads when it rains into the surrounding soils and waterways (other materials such as cullet (crushed glass) are also recycled into roads - one transport engineer once called roads "horizontal landfills"). Tyres can also be shredded and used as a soft surface beneath playground equipment - although this use can get children's clothes dirty (but the black from tyres doesn't stain).
Around the home or in your local community, you can do your own recycling of old car tyres. Here is a list of possibilities:
1. Use an ordinary car tyre to make garden ornaments. If you can find a way of cutting the tyre and if you are clever with paint, tyres can be made to resemble swans.
2. Any sized tyre can be made into play equipment. The most basic type of play equipment possible with a tyre is to tie it to a stout tree branch and make it into a swing (it can be oriented so it lies horizontally or vertically - both orientations work and each has its individual challenges and limitations for play). Larger tyres from trucks or tractors make excellent sandpits that don't crack like commercial plastic ones and are often deeper. A 4x4 tyre by itself can have a lot of potential for play - children can roll it around like a large and heavy hoop, they can sit in it and pretend its a boat, they can turn it on its edge and try to ride it like a horse (which offers a challenge - it moves and you have to try to balance on it)... Smaller tyres can also be used as hoops or as targets. With a bit of imagination, it could be possible to create a whole playground out of old tyres. A playground this writer knew as a child had a pyramid (all right - cone, for those mathematicians out there!) made from tyres bolted securely together, with enormous tractor tyres at the bottom and car tyres up the top. You could climb up the outside of the stack or down the inside of it.
3. Because tyres are black, they absorb heat. This makes them very suitable as garden beds for things that like warm soils (e.g. potatoes and yams). To stop weeds coming up from underneath, place a thick mat of plastic or newspaper (more recycling/reusing) down beneath the tyre, then fill the tyre with soil and compost. And plant your vegetables. You can stack the tyres to whatever height you want - a stack of larger tyres can become a raised garden bed, or you can add one extra layer above the soil and put a "lid" of clear plastic on the top to create a mini-glasshouse (if you do this, remember to (a)take the lid off in hotter weather to stop the plant becoming overheated, (b)water the plant, because the lid stops the rain coming in and the plastic beneath stops moisture coming up.
4. Still in the garden, tyres can be used to make compost bins. Just stack them up and pop in your garden waste. The warmth absorbed by the tyres means that the right temperature for beneficial bacteria will be maintained, but it may get too hot for a worm farm unless you ventilate the sides by cutting small holes in the tyres.
5. The tread on an old tyre is not enough to keep a tyre on the road, but it is still enough to keep a person's feet from slipping. It is possible to make your own very casual (!) thongs/flip-flops out of old tyres by cutting a piece of tyre to fit your feet and then adding holes for some rope to keep them on your feet. You may need to pad the top surface of the flip-flop to make them comfortable enough, and make sure you use soft rope so you don't get blisters. Alternatively, you can use old tyres to re-tread wellington boots or other footwear by gluing pieces of old tyre to appropriate places on the sole.