[Red Squirrel]

I want to break up a cement slab, roughly 12'x12' which is raised by I don't know what. When I look under it I see plywood but there is obviously something behind there, whether it's a beam or maybe piers. Either way, it's raised, which makes this a bit more tricky. It's maybe a foot off the ground.

What is the safest way to go about breaking this? Do I start at one end and walk on it and move backwards, or should I move into it and remove debris as I progress through? Also what is the best tool for this, a jackhammer or saw? I'm thinking jackhammer as with the saw there is a risk that it suddenly lets go while I'm operating the saw, with the jack hammer I'm just chipping off chunks at a time.

I'm going to assume there's rebar in there. There is also a large glass patio door nearby, should I protect that somehow? I've never used a jackhammer before so not sure how much debris flies out or if it's just dust. I do need to replace that door... just not now. :laughing:

 

[Ron6519]

Red, post some photos.
Ron

 

[Red Squirrel]

Here's some pics:

http://gal.redsquirrel.me/?level=album&id=34

 

[joed]

Depends how ambitious you are. I would start at the outer edge and work in towards the house. Being raised up off the ground like that it would probably break well with a sledge hammer. If there is a lot of rebar or mesh in then it gets more difficult. A jack hammer would also make quick work of it. Again rabar or mesh are going make trouble.
Either method would be supplemented by a large(six foot) pry bar to get the broken pieces out.

 

[Ron6519]

There looks like there's a iron pipe under the slab. What is it's purpose?
I seems like a very odd setup. Why would you pour a concrete slab over a plywood box? Is it doweled into the house?
It makes sense to start at the edges and work your way in towards the house.
I'd rent the jack hammer, unless you want a lot of exercise.
Ron

 

[DexterII]

Just a rhetorical question, but your crawlspace doesn't extend under that porch, does it? It's not bad with a sledge hammer, but if you end up renting an electric jack hammer, wetting the surface helps keep the dust down. Definitely protect the doors and windows with a few sheets of OSB.

 

[Red Squirrel]

Nope the crawlspace does not, at least I highly doubt it based on it's size. Though I've had my fair share of visions of what I may find under there, maybe some kind of secret bunker with a bunch of dead bodies or an abandoned grow op. :laughing:

So yeah I will go ahead with the jackhammer and work my way towards the house. I do have some plywood in the garage that I can set against the door while I work. The BBQ will come off obviously. I have two 2x8s I use as a ramp to get it off. Was fun dragging that in that alley through the sand. :laughing: Going to eventually put grass there to harden it and help keep the water away from the house.

 

[nap]

Nope the crawlspace does not, at least I highly doubt it based on it's size. Though I've had my fair share of visions of what I may find under there, maybe some kind of secret bunker with a bunch of dead bodies or an abandoned grow op. :laughing:
e.

probably just a spider habitat.

 

[Red Squirrel]

Yeah that's probably it.

I just hope that's not where the chipmunk lives. Poor thing will get a rude awakening when I start up that hammer.

Oh and that metal pipe, it's hard to tell but I think it's just loose in there. I hope it's not the gas line... lol. I doubt it though. either way, I will have to "call before I dig" just to be on the safe side. With the gas meter there, the gas line is around. I doubt it would be passing above ground though, it probably goes down a couple feet at the meter before it turns.

 

[oh'mike]

Red ---An angle grinder with a cut off wheel will help you to quickly cut any steel rebar or mesh.

They are very cheap---and a handy tool to have around the house.---Mike----

 

[Red Squirrel]

I've been thinking of buying one of those actually, they can come in handy for various uses. They are basically like an oversized dremel right? I can put various cutting/sanding bits on them? Or are they exclusively for cutting metal?

There's angle iron going all around this slab so I'll need it for that most likely. Good news is, I don't think that angle iron or any of this slab is going into the house structure, so when I get near the house it should just fall out. Worse case scenario I do have some spare bricks if I need to do any repairs to the house. At the end a new deck will be going in anyway.

 

[oh'mike]

A 4" angle grinder will hold wire wheels/cups---Diamond cutting wheels----steel cut offs---concrete cut offs--sand paper disks---and a ton of other handy accessories.

I have a couple in daily use that cost less than $20---If you use it for nothing more than cleaning you BBQ grill they are worth the cost.