"Formigão" is the mass similar to concrete, in which cement was replaced by lime.

It is made like "taipa", the mortar is compressed between removable wooden molds, that are removed after it is completely dried, thus forming a wall of unburnable, naturally isothermal material.

"Formigão" should only be plastered and treated with burned lime plasters or through direct whitewashing so as to be protected against the influence fo the atmosphere, mainly against water.

As it is easily ruined by water, it could only be made upon normal stone foundations, generally schist about 0,60cm above the ground, from which the wall was built. Thus avvoinding rising humidity.