White wash

[professor]

I remember when the barns and ouit buildings were white washed with a lime/water solution. This left a chalky white coating. I am wanting to white wash a barn and I have the following questions:
What are all the ingredients in this solution and the mixture ratio?
I want to spray it on therefore will a pto pump sprayer work? (the barn is approx. 20 feet high)

Thanks for any information you can give me.

 

[RedRocker]

My wife used to have to white wash the trees when she was a kid, I'll see if she remembers the mix.

 

[tallyho8]

We used to just mix it with water till it got to a consistency to brush on. Never measured anything. Not sure if it can get thinned enough to use a sprayer.

 

[waynokakid]

Here is a recipe from an elderly farmer I know. Make sure you use hydrated lime.

Mix in a large bucket, a five gallon paint bucket is ideal:
3 large coffee cans of hydrated lime (about 12 cups)
1 pound or 1 small coffee can of salt (about 4 cups)
2 gallons of water
When you mix this together, mix a little lime/salt, then a little water, then a little lime, etc. It you just dump it all together it's like stirring boat anchor. You should let the mixture sit over night, but we usually just use it right away and have had no problems.
The white wash should be fairly watery, remember it's a wash, not a paint. Give it a stir once and a while as you use it.
To use the white wash, just get a big brush and slop it on. Don't worry about getting it on your clothes, it washes out very easily. It may seem like it's not covering very well as you paint it on, especially on new pine 2x4s, but it will whiten up considerably when it's completely dry, be patient.