Redoing garage floor questions

[thapharm]

Hey guys so it has been about a year since my last post and I am about to take the plunge just have a couple questions. I am going to start tearing out my garage floor but am nervous since the cracks go all the way through the foundation. Should I cut around the edge with a concrete saw before breaking up the old slab? The way the garage was built was that there are the footers and the slab with the blocks sitting on the slab which the walls are built on and it makes me nervous. Here are some pics of the cracked all to hell floor. Let me know what you guys think. Thanks!

http://imgur.com/a/d2V7Y

Tom

 

[Dan in Pasadena]

Tom,
I don't understand what you're describing. Your garage floor slab and wall footings are one monolithic concrete placement? Then concrete block were placed in top of the slab around the perimeter as some kind of curb, with the wood framing on top of them? You're saying the footings and the slab are NOT two different concrete placements, right?

If you cut the slab as close to the block as you can you will need to tie the replacement slab to the footings/block remaining by doweling into it with rebar and epoxy. If I were you I'd consult a structural engineer.

My 80+ year old garage is sitting directly on the slab with no perimeter footing. It's cracked much worse than yours and in fact a corner of the slab has cracked off and settled resulting in the cracked portion sticking up almost an inch...so apparently there is no rebar in the slab! I've thought many times about saw cutting out the slab but I think the truly correct way to fix it would be to remove the slab entirely, underpin the whole structure while digging a perimeter foundation then pouring back footings and a slab within. Too much work, too much expense, so I will live with it as it is. You MAY want to consider repairs rather than replacement.

 

[thapharm]

Hey thanks for the reply! So here let me try to explain it better...I have the footings around the garage and then the 4in slab. On top of the slab and footings they stacked cinder blocks like 2 high then the walls up. The ground has shifted where the slab blocks and footings on like 3 sides of my garage are cracked all the way through. Does that make sense?

 

[rburke65]

If you are sure that the floor is under the studed wall then you would probably behove you to cut the perimeter. Also might be a good idea to post this in the floor section. Good luck.

 

[thapharm]

The picture with the weights is the floor going through the block all the way down through the footing

 

[thapharm]

Top layer is block second is the footing both cracked
http://imgur.com/a/LnizF

 

[Cyberbear]

It seems pretty evident from the pictures that the only viable option is to raise the garage up and have the existing concrete taken out and then form it up and pour a new slab and footings with the necessary re-bar. Hopefully the wooden structure is still sound and can be reused. Don't try to save a few bucks by cutting corners and skimping.

 

[6t7gto]

I would dig a test hole on the outside to see how deep the "footings" are.
My bet there is no footer. Just a monolithic pour.