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You are here: Home arrow Articles arrow Make your own arrow Soap Making: a beginner's guide


Soap Making a beginner's guide

Written by Sally_in_Wales

This soap recipe is aimed at those who have not made soap before, and is an all olive Castile soap. This is a soap that can be traced back to at least the twelfth century and is a very mild, gentle soap suitable for laundry as well as cosmetic use. It is a white soap that takes scents well, so a good all round soap for your first attempts.

Soap-making - precautions

Please make sure you fully understand the following points before starting:

1. Lye is in this case caustic soda crystals. It can often be bought from larger chemists where it is sold as a drain cleaner. Never use a ‘brand name’ drain cleaner instead unless you are certain that it only contains caustic soda. Boots often have it in the household cleaners bit.

2. Always add lye crystals to water, Never the other way around (it could spit). Lye and water generate a lot of heat and nasty fumes, best step outside to mix it.

3. Lye in any form is strongly alkali and can burn skin, if you splash it on yourself you will notice itching first. You can neutralise this with vinegar and then wash the area well. (Keep an open bottle of vinegar to hand when soap making as a precaution.)Wear rubber gloves as well and consider eye protection.

4. Lye reacts with some metals, I recommend you stick to glass or stainless steel jugs and bowls when making soap.

5. Raw (freshly made) soap is also too alkaline for use immediately. Give it time to mature and the pH will come down. The traditional way to tell if your soap was mild enough to use was to touch some to the tip of your tongue. If it is still caustic, it will ‘bite’. Use caution if you decide to try this approach andnever try it the day you unmould your soap! It will take several weeks for your soap to mature enough to try this with any degree of safety.

Basic Castile Soap Recipe

1kg Olive oil
126g caustic soda crystals
300g water

Weigh and measure all of your ingredients as precisely as possible. Add the crystals to the water (never the other way around) and stir. Warm the oil over a low heat (ideally aiming for hand hot, but don’t try sticking your finger into hot fat).

Pour the lye mixture into the oil after giving it a few moments to cool down, then start stirring gently with a metal spoon or baloon whisk. The lye will start to react with the fat to form molecules of soap and glycerine, in practice it will look a little like thin custard.

You are looking for the moment at which the mixture leaves a trace; this is simply the point at which you can see the trail left by the motion of the spoon for a few seconds. This will take up to 45 minutes depending on the fat you are using.

At this point pour it carefully into a mould (a small plastic food container works well) Wrap the whole thing in a towel and leave in a warm place to finish reacting and setting.

As it reacts it will pass through a gel phase, where it generates a lot of heat and goes darkly transparent. It will slowly cool and become opaque after this. Two days later you can unmould the soap and cut it into bars. It is not ready for use yet! It needs to be wrapped in grease proof paper and put safely away (an airing cupboard is ideal) for at least two months during which time the pH will decrease and the soap will become gentler on the skin.

This soap is usually very soft when first made, it will get harder as time passes and old Castle can be tough as nails.

You can use it as laundry soap before it is fully cured, just grate a bit down and use around a tablespoon of grated soap in the machine, with a half cup of white vinegar in the rinse aid drawer.

Making your home-made soap smell nice!

You could try storing the wrapped bars in a bag of herbs to impart a delicate scent.

Just before pouring the soap, you can add some dried herbs, or oatmeal, or honey (may turn the soap reddish brown!) or an essential oil (choose one you know is fairly safe- and you will need between 5 and 10ml in a batch this size)

Once the soap is cured (wait at least 2 weeks and you can do this bit) you can grate it finely, mix in dried herbs or spices, moisten it either with boiled water, or herb tea or rosewater and squidge it into 'soap playdough'. This can be pressed into moulds or rolled into calls and gives a good way to try several scent variations without having to make lots of batches of soap.


Any questions? Visit the forums to discuss this article and get tips and advice from other soap makers - Soap Making - a beginner's guide

If you still don't feel up to making your own, or would like to see what this type of soap is like before having a go, Sally sells traditional soap which has passed modern safety tests - visit Sally's site for more information