Showing posts with label plastering. Show all posts
Showing posts with label plastering. Show all posts

Tuesday, 20 April 2010

Horse shit for earthen plasters

We are stuck in a perpetual holding pattern for planning permission (licença de construção). They (the Authority/ies) believe they must create more layers of complex paperwork and regulations for building, renovating an existing structure. And doing it by ourselves, a self-build? Illegal we are told. We are forced to use contractors and to show how much we pay each of them every step of the way. Enough to drive you to drink and drugs in a spiral of self-degradation.

Instead we have decided to embrace the flow of things and get on with building other things, other places on our land. Of which there are plenty. And we can do this without asking for The Authority's approval.

Which takes us back to the garage. Local builder Machado plastered one half of it last December, with our sand - lime mix of 5:1 (that's 5.5 buckets of sand to one of lime: quicklime or cal viva as it's called here). This is the mix we had used for pointing the main house. It works and I foolishly thought it would be good for plaster too. It has held up OK, but I've since learned you need more fibres to hold it together. (In the old days they used horse hairs and the like).

So this time our mix has fibre: from horse poo. Plenty of little grass "fibres", and quite a few actual hairs that found their way in! Donated kindly by Donald and Eleanor, this poo should really have been allowed to dry out a bit, but we are impatient, hasty (we being me). Paulo, senior techy adviser, had this idea, and we all agreed that it was far better than buying anything plastic or expensive.

So Monica got landed with the illuminating job of crushing up the pleasant offerings...






While The Kids and Me played for days until we learned how to hurl this mix onto the wall till it holds fast - seeming to defy gravity by holding there, then after a while allowing itself to be shoved around into a rough uniform surface. OK, we achieved anything but a smooth finish, but hey this is workshop / toy room (my toys, not Kira's) we're talking about.

Much fun had, photos will say the rest.
Paulo (earth plaster pro) made sure we kept spraying water on it too avoid it curing (drying) too fast. And doing it himself when he saw we were going to forget (OK mostly, this is the case).



Quick lime steam bath and dust cloud. Dodgy stuff to work with: super dangerous for eyes and bare skin. (Which is why Nikita is wearing his...? Staying at a safe distance of course:)
















OK here's the magic recipe: 5 parts sand, 1 each of earth, horse poo and lime. Lime being the last one to add to the mixer. Add water in doses with the sand, so it's already saturated. Don't let it go too wet. The earth will improve the consistency. Make sure you break up the little clay balls in the earth (we used a clay-rich soil, about 25% clay content). Break down the horse manure balls a bit so they dissipate in the mix. Cover eyes and hands, and wear a mask when adding the lime. It will react with the water in the mix and get really hot. It seems to be a crazy thing to do, but it's not. It'll be OK. Relax. Walk away from the mixer for a few. Breathe.


Then Paulo and I built these funky shelves - posts made from alder (the reddy one) and ash, from our river land. Placed on rocks with steel pins to avoid contact with water and floor damp. Water infiltrated from the back of garage all winter.



Spraying the wall down with the new jet-pack!

Funny thing is, as it cures, it's going much lighter, changing from a dark tan to a light brown.














Like this detail around the window myself:)


And here is how the wall was before we started. The old earth pointing around the rocks would fall out all over you if you touched these walls. A proper lime pointing job replacing this would have been possible, but really boring, taking way longer, and the kids would have walked off in search of something more engaging. Anyway, we kinda like this warm colour and curvy walls. We are maxed out on stone...