|Blocks are stacked and braced. Rebar is inserted during stacking.|
|Plywood and sprayed foam prevents blow-outs when the concrete is pumped in from overhead.|
|The poured concrete fills voids in the block to make a steel reinforced concrete grid.|
Over the years several companies produced blocks here including Amazon Gridwall and Rastra .
In one notable case a builder somehow obtained forms to make the blocks and home-brewed a version of them in a below-the-radar near westside factory. The story goes that he then built and sold houses made with the block without informing either the building inspectors or the new homeowners. (Assuming that the blocks were of good quality, that would be a very pleasant surprise for any homeowner.)
The blocks sold by our presenters however are produced on the up and up out of state.
ICF blocks produce a structure that is extremely quiet, insect resistant, tight and energy efficient. The walls stand up to windstorms and earthquake ( a much more common occurrence here in South Texas due to fracking).
Another distinct advantage of building with ICF blocks within the city limits of San Antonio is that code and building authorities have approved many buildings utilizing them.