Egg white in earth or lime plasters

We have poor earth for building (on-site soil is silty sand and the best we can source is acceptable but not great). Our earthen plaster is very robust and hard, but a bit too dusty and susceptible to water. We are only using it on interior surfaces but that includes our "exterior" wall that will be enclosed as a sunroom.

We have a ton of eggs (24 chickens and stopped selling eggs because we are too busy building). We have a gallon+ of egg whites in our freezer.

So I have been looking into using egg whites in our plaster. Below are some links I found on the subject, and I thought others might be interested. Most of them are about egg in lime plasters, but some are about egg in clay.

We have done some small tests. We plan to use this just for our color coat: 1/8" covering our 1" of straw/clay plaster. It is lovely to work with; the egg makes the plaster feel more silky and smooth.

I think we will be using:
4 parts tannish pink fill dirt from concrete supplier (the "clay")
3 parts sifted red scoria dust as aggregate & color
1 part crushed char as aggregate & color & air quality / humidity stabilizer
1/2 to 1 part beaten egg whites for greater cohesiveness and water resistance

It's a nice dark chocolate / espresso sort of color.The attached pic shows a test. Background is an old straw/clay plaster sample that was left out in all kinds of weather for weeks (so our plaster looks better than that). The color coat samples are dirt + scoria on the bottom, dirt/scoria/charcoal on top left, and dirt/scoria/charcoal/egg top right, not dry yet. The straw was just blown onto the samples when they were wet; we won't have straw in the color coat.

If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

Links:
https://misfitsarchitecture.com/2015/01/22/its-not-rocket-science-11-keeping-the-water-out/
https://www.researchgate.net/publication/320738514_Preliminary_Studies_on_the_Development_of_Lime-based_Mortar_with_Added_Egg_White
https://www.atlasobscura.com/articles/filipino-desserts
https://30stades.com/2020/07/15/centuries-old-lime-egg-wall-plaster-technique-being-revived-by-chettinad-masons-tamil-nadu/
http://craterre.hypotheses.org/files/2018/05/TERRA-2016_Th-4_Art-396_Pedergnana.pdf

I don't know anything about using egg whites, but all your samples look wonderful!

This is fascinating Kimi,
Using Eggwhite in Plaster is something I would never have thought of!
I would have been worried about the egg starting to smell, but I suppose this isn't a problem? I've heard about egg in paint to give a shine, so this is a logical progression.

Kimi Iszikala wrote:We have poor earth for building (on-site soil is silty sand and the best we can source is acceptable but not great). Our earthen plaster is very robust and hard, but a bit too dusty and susceptible to water. We are only using it on interior surfaces but that includes our "exterior" wall that will be enclosed as a sunroom.

When I read the title I thought it made reference to making the plaster mix as white as egg shells.

When I did read it all, I thought others with more knowledge than I all over this like snow on my bestest ski mountain.

T

If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

I was in a monastery on the river Krk in Croatia, on the Dalmatian coast. They had a cistern to catch rain water because the river water is too hard to drink. It was built in the middle ages and still functions to this day. The mortar they used to seal it and make it waterproof was made with egg whites. Over 500 years and the surface is still smooth be it full or empty. Seems a good reason to give it a go.

Jason

Jason Learned wrote:
If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

I was in a monastery on the river Krk in Croatia, on the Dalmatian coast. They had a cistern to catch rain water because the river water is too hard to drink. It was built in the middle ages and still functions to this day. The mortar they used to seal it and make it waterproof was made with egg whites. Over 500 years and the surface is still smooth be it full or empty. Seems a good reason to give it a go.

Jason

I'm curious if you know about all the materials used (clay, lime, fired bricks, rocks, etc) - could be amazing info for future cistern builds (and maybe bathroom tubs and showers)

The more I learn about natural building, the more I realize how absolutely dumb we, as a global society, have become. So much knowledge has been lost  

I say it's time to revive it all and start trying to do things the right way again!

Jason Learned wrote:
If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

I was in a monastery on the river Krk in Croatia, on the Dalmatian coast. They had a cistern to catch rain water because the river water is too hard to drink. It was built in the middle ages and still functions to this day. The mortar they used to seal it and make it waterproof was made with egg whites. Over 500 years and the surface is still smooth be it full or empty. Seems a good reason to give it a go. Jason

===========

Do you know if the finish needs a refresh, Jason, or has it been self sealing for all that time?

Terry

Terry Byrne wrote:

Jason Learned wrote:
If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

I was in a monastery on the river Krk in Croatia, on the Dalmatian coast. They had a cistern to catch rain water because the river water is too hard to drink. It was built in the middle ages and still functions to this day. The mortar they used to seal it and make it waterproof was made with egg whites. Over 500 years and the surface is still smooth be it full or empty. Seems a good reason to give it a go. Jason

===========

Do you know if the finish needs a refresh, Jason, or has it been self sealing for all that time?

Terry

From what they said it has been in use since it was put in. The stonework covering the cistern looked undisturbed and matched the other walls near it. And the Charles bridge in Prague has not been altered since it was built as well. So it seems to be a permanent thing.
But opus signinium was used in the aquaducts of Rome and they still function where they are not destroyed, and they used geopolymer technology instead of egg whites.

Tristan Vitali wrote:

Jason Learned wrote:
If anyone has any experience or info about egg plasters, I'm all ears! Or scoria / char as aggregate, for that matter...

I was in a monastery on the river Krk in Croatia, on the Dalmatian coast. They had a cistern to catch rain water because the river water is too hard to drink. It was built in the middle ages and still functions to this day. The mortar they used to seal it and make it waterproof was made with egg whites. Over 500 years and the surface is still smooth be it full or empty. Seems a good reason to give it a go.

Jason

I'm curious if you know about all the materials used (clay, lime, fired bricks, rocks, etc) - could be amazing info for future cistern builds (and maybe bathroom tubs and showers)

The more I learn about natural building, the more I realize how absolutely dumb we, as a global society, have become. So much knowledge has been lost  

I say it's time to revive it all and start trying to do things the right way again!

I can't be certain, but they most likely used sand with grog and lime putty. The lime created is not all equal, the limestone came from different mines and the mineral impurities from some forms of limestone make a better mortar.  Now that is something that would be great to relearn! The opus signinium used calcined terra cotta or misfired tiles crushed. The clay had either phillipsite or analcime as a flux in the clay; this powdered ceramic would be mixed (three parts) with one part lime putty and the calcium would replace the sodium or potassium atoms leaving them as free ions to break and reform silica alumina bonds and create a solid plaster that held water.

I downloaded a bunch of books from the late 1800's about building stuff and some had different concrete and mortar formulae. I really have find it again sometime and write them down.