Being a natural fibre, wool is very breathable and is a great cover over a fitted nappy - for nights especially. A wool cover works by absorbing any moisture not absorbed by the nappy itself and evaporating it. It's a great option if you're experiencing leaks overnight.
Lanolising wool covers will increase their water resistance and will also help neutralise any odours. A chemical reaction occurs when urine comes into contact with the lanolin in the wool - it essentially neutralises the ammonia in the urine by breaking it down and evaporating the remaining water, so that once a wool cover is air dried it's fine to use again. You only have to wash and re-lanolise once the urine smell doesn't go away, indicating that there isn't enough lanolin in the wool to react with the urine.
Wool covers need to be lanolised once a month or so or if they start being less absorbent. Well lanolised covers used in rotation should last at least a week or two (if not longer) between washings (unless soiled). Between wears make sure you air out the cover. Hand wash in wool wash. If you can find a lanolin rich wool wash you may not need to lanolise your cover every time you wash. Do not subject your wool covers to rapid changes of temperature - it will 'shock' your wool - and don’t agitate the covers – this can cause the wool to felt. After washing you can lanolise.
Only lanolise clean wool covers. Most people lanolise straight after washing while the cover is still damp.
Use a small amount of solid lanolin (about 1/2 teaspoon per cover - more if they're wool longies belonging to a toddler) and melt it into hot water.
See how the melted lanolin floats on top of the water like a yellow oil? You can move ahead with lanolising without adding anything else, but (especially if you're new to lanolising) you can end up with patchy coverage.
To help disperse the lanolin through the water, you can add a couple of drops of baby shampoo or wool wash to the mixture and stir it through until there's no more yellow grease on top of the water. The mixture will be cloudy, maybe even milky in colour (depending on what you use to help dispersion). If there are still yellow spots of lanolin on top, add another drop of wool wash/baby shampoo and mix again.
The white specks ('floaties') you might just be able to see in the photo above are caused by emulsified lanolin solidifying. It's OK if this happens, though you'll end up with small white patches on your cover after lanolising (like in this photo), which won't be obvious when dry. If it bothers you, adding ice cubes to your mixture straight after the lanolin has melted and dispersed may prevent floaties forming (can you tell they don't worry me so I haven't tried this?).
Back to our lanolin/water/dispersing agent mixture: Add this mixture to a sink or basin of enough warm water to immerse the covers in. Give it a good stir, making sure the lanolin is dispersed well.
You don't want to add your cover straight away - wait until the water is lukewarm or at room temperature as you don't want to put your cover (which has just been washed) into water of too different a temperature - it won't like it.
When the water is at room temperature, place your cover (I prefer inside out) into the basin and submerge. If you're very gentle, you can turn your cover inside out and submerge it again. Be careful though, as handling too much when wet can cause your cover to felt. Let your wool cover soak in the basin/sink for at least 30 minutes. Some people like to let their covers soak for several hours, or overnight.
Drain out the water and gently press the cover to remove water. Do not wring or squeeze hard. Wrap the cover in a towel to remove as much moisture as possible. Don’t rinse. Lay it out flat to dry out of the sun. I like to pop my covers to dry on a cake rack so the air circulates around them.
When dry, your cover may feel slightly sticky or tacky - this is OK! This means your cover is well lanolised. The tackiness will soon wear off.
New wool covers might need two lanolin treatments to become fully water resistant‚ especially if being used for a heavy or nighttime wetter.
Spray lanolin is an easy way to top up the lanolin between washings, or if you don't need a heavily waterproofed cover.You can find our range of wool covers here and lanolin here.