Now that the walls are pilled up we had to decide on the plastering. Last year we made two trials and both had its advantages and disadvantages.
We tried to make a plaster with the sand from the construction site and mix little mortar to it. The idea is to use the most possible local material to avoid transport and material cost. The other advantage is that mortar based plasters are water proof.
In Baja California there is little rain, but in hurricane season rain can be so heavy that earth walls can literally be washed off.
On the other hand the disadvantage of mortar or cement based plasters is that they don’t let any vapour pass the wall; the wall can’t breathe and humidity can accumulate.
The other plaster we tested was earth plaster. Earth plaster has the advantage that it absorbs well humidity and has advantageous thermic properties. Earth plaster breath.
In view of our experimental hack-shack we decided to apply both plaster techniques. On the outside we applied the sand and mortar solution to have a waterproof shell for hurricane season and on the inside we will use earth plaster to improve the housing climate and feeling.
The south wall being plastered…
Now that we have the electrical conduits and hydraulic wall passing with the wire mesh put in place we were able to apply all the plaster. Since the sandbags are uneven there is a larger material requirement of plaster. This is a disadvantage of the sandbag construction to be considere.
North wall is the most complete wall, protecting from the winter winds.
West wall being plastered. All the utilities as, water storage, dry toilet, biodigestor, solar water heater as well as battery storage will be placed on the west side of the house.