Wednesday, November 14, 2012

First shot at S.B.C. (Surface bonding cement)

Once we had dry stacked all the 12" blocks that made up the front frost footings I needed to surface bond them together. The surface bonding process is not a new technique and studies have shown that it is stronger than a mortared wall. I was mostly attracted to the fact that I did not need to be a brick layer to dry stack cement blocks, and with the use of SBC I could make a wall that was stronger than mortar with no prior experience.

The process is started by mixing a product called surface bonding cement and water. I used Quickbond (a Quickcrete product) and it worked well. Be sure you do not get it on your hands. I got big time chemical burns from it in a real short time. After mixing the batch to my desired consistency I would fill a pail and trawl the SBC to the wall. It was fast and was not to difficult. Since the coating is only about an 1/8 - 1/4" thick you need to presoak the wall, and also keep the SBC wet down for as long as practical to let it dry slower. The SBC needs to be applied to both sides of the wall to be effective. I should also mention that it is water proof once it is set.

This is how you get running water with no electricity to the build site.

The SBC is applied to full thickness in one coat.

Hear you can see that I presoaked the wall ahead of applying the SBC.

See how the SBC is drying. I tryed to keep it damp for 4 hours or so after application.


  1. 1. Why did you presoak the wall?
    2. Was the sbc applied only to the north wall or all the way around?
    3. Why did you apply it to the inside of the wall and not the outside?

  2. I presoaked the wall to help slow the drying of the SBC. SBC is applied in a thin coat (1/8") and since the cemment blocks are very dry they suck the water out of the SBC to fast. Remember from earlier posts about concrete, the curing process is a reaction between water and chemicals. So if the water is taken out of the SBC to fast it stops reacting or setting up. This weakens the bond. With cement the slower the curing the better.

    SBC was applied to both inside and outside of all the block walls. As a matter of fact in our utility room the SBC is painted and that is our finished interior wall.