Hello. We are converting a former metal portable building used for a school classroom in to a living space. We have got all the site plans, remodel plans, electrical and foundation ECT. We are trying to do as much work as we can ourselves. We are used to doing remodel work ECT….but this is a first for cement like this. Question is…what is the best way to suspend the rebar cages so they will pass inspection. Can we use bricks? We are at an incline so all 4 cages vary in size from 4 feet up to 8 feet. They piers will be 36 inches around. Thank you.
Best Answer
Most inspectors will allow 3" dobbies, but really you should use 3" chairs to keep the rebar 3" clear off the bottom and sides. (The reason your engineer specified 3" is because of moisture protection and chairs allows less moisture than dobbies.)
I'd wire the steel in place at the top using a wood frame cage set 3" in on the sides and wire the cage to keep it from falling side-to-side. Don't wrap the wire around the steel more than once. Then after the concrete is installed, you can pull it out so no moisture penetration points.
By the way, I'd use 3/4" minus aggregate because of the closeness of the ties on top.
Also, you can use the wood frame cage to guide you when you set the 10" square steel plate. Make a template and it will fit perfectly in place when the "mud" is still wet.