improving an unreinforced, 30-inch-high CMU stem wall for a single-story residence..
improving an unreinforced, 30-inch-high CMU stem wall for a single-story residence..
(OP)
thread507-210389: Unreinforced CMU Foundations
In this previous thread, Oldpapermaker stated, "A few times each year I get asked to design modifications to a bldg, usually light frame walls with wood structural panels, that has a existing CMU foundation stem wall or bsmt wall that is unreinforced & ungrouted. Most of the time there is no bond beam at the top of the wall and no anchor bolts from the sill plate to the wall below. I usually tell the client that they have to figure out how to reinforce the wall or replace it."
So, I have a friend who needs to figure out how to do this, and I also told him he needs to reinforce the existing unreinforced CMU 30-inch-high stem wall and anchor the sill plate to the wall. Would appreciate suggestions on ways to do this. I'm thinking something like 1) drill oversized holes in CMU blocks from interior, insert c-shaped bars thru holes, and fill CMU with cement-water grout, then 2) construct 4-inch thick reinforced concrete wall poured directly against the interior side of the existing CMU with the reinforcement cage tied to the afore-mention c-shaped bars, and 3) anchor the sill to the CMU wall which should be adequate because it's been reinforced by the interior CIP wall. Also, I think he needs to add continuous CIP foundations beneath his two primary interior walls, and tie these to the perimeter CIP walls. Does this sound like a reasonable approach for safety for this two-star residence?
In this previous thread, Oldpapermaker stated, "A few times each year I get asked to design modifications to a bldg, usually light frame walls with wood structural panels, that has a existing CMU foundation stem wall or bsmt wall that is unreinforced & ungrouted. Most of the time there is no bond beam at the top of the wall and no anchor bolts from the sill plate to the wall below. I usually tell the client that they have to figure out how to reinforce the wall or replace it."
So, I have a friend who needs to figure out how to do this, and I also told him he needs to reinforce the existing unreinforced CMU 30-inch-high stem wall and anchor the sill plate to the wall. Would appreciate suggestions on ways to do this. I'm thinking something like 1) drill oversized holes in CMU blocks from interior, insert c-shaped bars thru holes, and fill CMU with cement-water grout, then 2) construct 4-inch thick reinforced concrete wall poured directly against the interior side of the existing CMU with the reinforcement cage tied to the afore-mention c-shaped bars, and 3) anchor the sill to the CMU wall which should be adequate because it's been reinforced by the interior CIP wall. Also, I think he needs to add continuous CIP foundations beneath his two primary interior walls, and tie these to the perimeter CIP walls. Does this sound like a reasonable approach for safety for this two-star residence?






RE: improving an unreinforced, 30-inch-high CMU stem wall for a single-story residence..