Lime Wash

Lime is a natural substance. But it is caustic and can cause burns, so make sure you are properly protected before using or slaking it. The health and safety guide for lime is here.

Lime Wash: How and Why to Make it.

Earth plaster is beautiful. It has a warm, rustic texture that's soothing to the eye and pleasing to touch. I loved my grainy brown walls, and so did most other people, and I hummed and hawed about coating them in a lime wash. In the end I did. Why?

A lime wash is like the icing on your mud house cake. It holds the crumbs of sand on the wall, seals the plaster and keeps the bugs out. While I adored the rough mud texture of bare earth plaster, after a year I noticed issues. None of them were major. But here are the four reasons why I lime-washed.

1. Light. Earth plaster is rough and ready. It's the Hugh Jackman of the plaster world. But it has a dark side (don't they all). While I love cosy, warm caves, I also crave light. Earth plaster tends toward the dingy.

2. Dust. Without the lime wash, earth plaster alone creates an incredible amount of dust. I diligently swept my house every morning and never seemed to make significant inroads into the dust deposits. Window sills, door edges and alcoves were a devil to keep clean.

3. Insects. Lime is an insecticide, and I noticed as soon as I coated my walls in a lime wash that the amount of bugs in my home reduced drastically.

4. Repairing earth plaster is far more labour-intensive than simply whitewashing with lime. It requires another round of stomping of the mud, more mess in application and a longer drying time. No matter what you put on the walls, you need to maintain them. Lime is faster and easier for sure.

How to Make Lime Wash

Make sure you are dressed appropriately to protect yourself. Put a pint or two of lime putty in a bucket. Add casein (you can buy it as a powder or make your own from milk) or seasalt (about one part to 5 parts lime putty). Then slowly add water and stir (or whisk) until you've created a smooth, thinnish white paint.

Note: You need the salt or casein to help seal the limewash, otherwise your whitewash remains dusty, and can leave marks on clothes.

ANOTHER TRICK!
You can also add skimmed milk to the lime putty instead of casein powder to create an amazingly hard, protective finish. The casein in the milk reacts with the lime to form a strong, dust-free shell. 

COLOUR
I wanted to avoid the traditional whitewash look and hoped to create a more wheaty colour. We tried out various natural home-made colours including turmeric, cinnamon and tea. Strong Turkish tea seemed to work the best. You can of course also buy natural paints to add to your lime. Just note that lime always whitens as it dries, so your finished colour will be far paler.

Three Reasons You Might Not Want a Lime Wash

Do I regret liming? No, but it's a close call. Here's three reasons you perhaps wouldn't want to lime your walls.

1. No matter what you do, lime always tends to whiteness. Strong, vibrant colours are hard to create naturally. So if you want that, you'll need to buy some natural paints. Even so, expect a high level of fading.

2. Lime definitely doesn't emit the same warmth as earth plaster, though lime does create another type of magical atmosphere. And there are tricks for increasing the cosiness, things like leaving earth plaster skirting boards, earth plaster sculptures and alcoves.

3. As mentioned above, if you don't add enough casein, glue or salt, it can leave white dusty marks on your clothes or furniture.

How eco-friendly is lime? Isn't it just as bad as concrete?
Want to know how to use lime in more depth?
If you want to explore the Amazing World of Lime further, and learn how to use the white wonder, I have a new course out.  It includes videos, slideshow lectures, and PDFs, and is completely downloadable.
I always update and add sections to my courses over time. Once you’ve enrolled in the course you’ll have access to all future updates.

The course includes:

  • Which kind of lime you should use for which job and in which climate
  • How to slake quicklime
  • How to mix and apply lime render
  • How to apply lime mortar and some tricks for a clean finish
  • How to deal with mortar guns when using lime
  • How to mix limecrete 
  • How to make a limecrete floor
  • How to use limecrete with tiles
  • How to create lime paint or lime wash with and without colours