Root cellar: surface bonding cement

We’ve had more than five inches of rain during the last nine days. In between some of the showers and storm, I’ve been able to work some on the root cellar. The frequent rain has been frustrating in that it’s kept me from getting things done like I want to, but that’s the way it goes.

The blocks are all stacked for the walls. I was able to fill 12 cores in the walls last week when we had a mostly rain-free day. I filled six more cores yesterday, all that will be filled. Last Thursday I was able to apply the surface bonding cement to the outside wall toward the hill on the back of the root cellar. That night we received some very heavy rain (over an inch and a half of it) which caused some mud to break free on the back wall of the excavation. Not too much, but I was glad to have the wall done on that side.

Today, I installed the PVC through the end walls to which I will connect the fresh-air vents for the cellar. I used concrete and mortar to fix them in the wall and cover the holes around the edges.

Then, I finished parging the rest of the outside walls. It was muddy down in the hole around the outside of the cellar walls. The dirt is mostly clay and sticks to my boots like crazy. I wore my muck boots since they can be cleaned off fairly easily.

After finishing the outside walls, I changed shoes and began on the inside. I was able to parge one inside wall, an end one. I hope to finish the other three walls tomorrow.

I mixed the surface bonding cement in a wheel barrow today, using a garden hoe. It worked fairly well. Previously, I mixed it half a bag at a time in a five-gallon bucket using a paddle mixer with an electric drill. That method actually worked better, but my mixer needs repaired. So, I didn’t use it today.

The key is getting the right amount of water in the mix. If it’s too wet, it’ll slump off of the wall. If it’s too dry, it takes a lot more effort to trowel it on the wall. When it’s mixed just right, it trowels on smoothly and stays where it’s supposed to. It’s been a trial-and-error process getting the mix figured out.

Surface bonded concrete block walls look nice, I think. Better than regular, mortared block walls. It’ll be nice to see them all complete. At that point, I’ll start backfilling.