# Forum Home Renovation Demolition  Demolishing concrete slab

## Blackpaw

We have two concrete slabs in our back yard that have to go to make way for a deck, One 3x3m, the other 4x2. Both are *about* 30cm thick, the 4x2m one has a layer of bricks on it. 
Have never done this before so not sure of the best way to proceed. My current plan is to rent a jack hammer and a skip for a week. And some Crownies (they'll be purchased, not rented).  
Once the slab are gone I'll have a big depression that will need filling - whats the best approach there? can I just get a load of cheap fill from a garden center or some such? 
Thanks.

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## notvery

not sure if its practical with the size of the slabs you have but i tried a jack hammer on a path my dad had built which was about 1meter wide by 20 long. he had laid the concrete in one go some how... and had used a layer of hardcore(half bricks old bits of concrete old metal pipes and the such like). there are tank roads weaker than this thing. spent a couple of hours the previous afternoon nibbling about 50cm off the end with the jack hammer... the next morning i thought "f doing that again." got the sledge hammer out and 6 foot crowbar whacked the path about 2meters away from the end 3 or 4 times, shoved the crowbar under the end of the path and pivoted it on some bricks and heaved... the thing lifted a little and a couple more whacks with the sledge i could lift the slab enough to prop it up and then the sledge made movable bits which became someone elses problem. whole job done in a morning. 
not anti jack hammers but sometimes there are other options that might be easier and leave your afternoon free to drink..  
oh i was a skinny 16 year old when i did the above so i didnt get to drink that afternoon... :No:

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## Blackpaw

Thanks notvery, I suspect some trial and error on my part. To be honest the moving all the concrete to the skip bugs me more - its a lot of weight to shift!

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## notvery

oh and dont listen when someone tells you to just get rid of it by putting 10kg in each of your neighbours bins each bin night. tempting tho it is. 
what are you going to do with the area where the slabs were? just chuck some turf down? or something more industrial? i guess that will change the fill options

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## toooldforthis

this is one of those jobs where I supress my scrooge and hire a bobcat and driver for half a day
he can clear the pads and re-level the site.
get some quotes - you might be surprised.

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## Sir Stinkalot

> this is one of those jobs where I supress my scrooge and hire a bobcat and driver for half a day
> he can clear the pads and re-level the site.
> get some quotes - you might be surprised.

  Agreed. I hired a jack hammer to break up a pedestrian path that was running around our house. It took much longer than expected and was a couple of weekends of jack hammer hire not just one. After it was all broken up I then started to try and move it. Perhaps I broke it up too well as it was a real pain to try and collect it to put it in a wheelbarrow. In the end I got a quote from a dingo digger guy and he laughed when he saw the effort I went to breaking it all up and said it would have been quicker for him to get rid of it before I broke it all up than after.  
If anything get some quotes and views before you commit to anything.

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## Marc

The biggest electric jackhammer you can hire is the Bosh Brute Breaker or Makita equivalent. 
I have one of those and I can tell you, you will be struggling to break 30cm of concrete, unless you hire a large industrial compressor and a pneumatic jackhammer like the one used for roadwork. (Don't even think about doing that) 
When it is possible that you are mistaken and that it is only 10cm and the edge has a beam around it, The best way to get rid of such lumps of old concrete is a concrete saw and a small excavator, bobcat or dingo. 
You can of course hire a petrol driven concrete saw and a small excavator but both require some skill. Large arms for the concrete saw and a bit of a learning curve for the excavator. No big deal, but perhaps the suggestions above to call a bobcat driver with a jackhammer attachment may be a sensible one.  
I called a bobcat once to rip up a bad job done by a paver dude, (paved over 15 degree sloping ground without leveling first.) and he turned up a few hours after calling him did the whole job in a few hours, took all the dirt away and charged a very reasonable amount.  
Having said that, I enjoy hiring large tools I don't have, like wood chippers and excavators and trucks. You may enjoy it too and who knows, it may be soft concrete and break easy. May be worth a try for not much money..

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## justonething

30 cm is a foot in the old language. That's some slab.

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## phild01

I would randomly verify the depth with the rotary drill.

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## Marc

Or, you could have some fun with Dexpan ... mm ... it rimes! https://www.youtube.com/watch?v=KgOtMQcMnH0

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## Marc

I suppose a 9/11 style demolition is out of the question? https://www.youtube.com/watch?v=eem7d58gjno

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## notvery

Would seem a little over the top for a 3x3 slab but i guess if you have some explosives just hanging around the place not being used it could work

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## Marc

> Would seem a little over the top for a 3x3 slab but i guess if you have some explosives just hanging around the place not being used it could work

  So true ... and you can always protect the house hanging some plastic sheets with tape  on the external walls!

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## notvery

Why bother the house will be fine. I believe the op is looking to replace the windows and deck so it could give him a helping hand on both counts.

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## Blackpaw

Wow, thanks for all the suggestions, most informative. 
The bobcat  idea is very tempting, but access is a problem. Its via 140cm wide gate  and a 15m path with a lot of foliage in the way. We could come in the  rear via the park but would have to demolish the back fence to do that -  last resort. 
I did wonder if the the 30cm was just a lip - I'll drill some test holes as suggested.    

> Why bother the house will be fine. I believe the op is looking to  replace the windows and deck so it could give him a helping hand on both  counts.

  LOL!

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## Marc

140cm is plenty for a smaller bobcat. Foliage ... lift the blade and automatically prune as you go ...  :Smilie:  
Taking one panel off a colorbond or timber fence is a 10 minutes job

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## Blackpaw

Ok, whats the best way to find a operator in Brisbane? any recommendations?

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