The Concrete Homes Council and the CFA were well represented in the World of Concrete Housing Megademo this year. In case you missed it, the Megademo covered two days of activity. The first day demonstrated the set-up and concrete placement for many of the technologies available in concrete housing. Day two focused on finishes showing the forms stripped away with concrete or special finishes exposed. In addition to RCF’s (Removable Concrete Forms), ICF’s, post-tensioning, tilt-up, and precast were also demonstrated.

How did they do that you ask, cast walls (and a deck) one day and strip the next? By using a special concrete mix called 4×4. The goal of this mix was 4000 psi in 4 hours. I don’t know if they got to 4000 psi (the temperature dropped to freezing overnight) but they easily had enough strength (over 3000 psi) to strip the forms. In fact, the interior of the Wall Ties and Forms setup, a 10’x 10’ room with deck above, was at a temperature of over 140 degrees F the following morning.

Two Concrete Homes Council alliance members were represented in the RCF demonstration. Wall Ties and Forms constructed their room and pumped it from the bottom using a special SCC design mix. Their project was finished with a sprayed-on finish. The other member of the CHC participating was Durand Forms. The Durand wall was an insulated sandwich wall using the T-mass System and a vertical thin brick system by Scott System to show how you can get a brick finish in one pouring operation.