# Forum Home Renovation Concreting  Price of Concrete Slab

## lisachan25

Hi, we are looking to rebuild our house and I'm just wondering what kind of price I can expect for the concrete slab, which is about 250m2 with a depth of 600mm. I'm new to these stuffs so please tell me if more information is needed. Thanks.

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## jago

If your slab is to be 250m2 at a depth of 600mm thats 150m2 of concrete which is massive ...are you sure your figures are for a house/correct? 
Slabs are normally 100mm thick with  footings 600mm deep 450 mm wide but they run on the perimeter and sometimes through sections so it is unusual to get a slab 600mm thick. 
150m2 @ $200  = $30,000.00 for concrete  + pouring and pumping your loking at 22 concrete trucks. 
plus steel and labour which would double your concrete cost this size of slab , allow  two weeks with about 6 guys to do ground  work steel and 3 stage pour of 50m2 at a time.

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## ringtail

x 2 with jago. Do you live in a industrial shed ?

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## lisachan25

sorry, 600mm is supposed to be footings, 100mm is the depth

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## ringtail

depends on how many and how wide your beams ( footings are) and if there are any piers  supporting the footings

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## lisachan25

footings are 300mm wide
i'm not sure about how many beams are there though, but its a stiffened raft slab system and its in a 4x6 grid

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## Master Splinter

It might be worthwhile seeing if your local TAFE has an owner-builder course, or getting the Alan Staines owner builder books (available from Bunnies). 
There's a huge lot you need to know, otherwise you run into little problems like the owner who proudly supervised his slab pour...without any plumbing penetrations.  It wasn't an insurmountable problem, just $5k extra that didn't need to be spent.

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## lisachan25

my dad is actually doing this as an owner builder and he also got the Alan Staines book, thanks for the suggestion anyway.
he just want me to ask around and see what sort of price we can expect

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## ringtail

I'll have a guess based on previous slabs, - $ 25 000 + / - $2k

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## lisachan25

we received a quote of 55000 including a root barrier, i'm guessing that's WAY over the top then...?

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## Master Splinter

Depends.   
Is it 'turn up on the day and pour', or is it lay reo and pour, or do site prep, lay reo and pour, or survey/site prep/reo/pour, survey/site prep/coordinate other tradies/reo/pour etc etc etc. 
The easy way to work it out is to calculate the volume of cement, the number of sheets of reinforcing fabric, the number of lengths of trench mesh or reinforcing bars and so on and ring round and get prices.   
250 square meters of 100mm concrete is 25 cubic meters, or $5k of concrete assuming $200 per cubic meter; about 18 sheets of F72 mesh at say $60 per sheet gives you another $1000 odd; then add the cost of trench mesh, reo, bar chairs, vapour barrier, tie wire and all the other bits and pieces.   
A (very) rough guide is to multiply the cost of materials by three, and that'll get you near the ballpark for your final cost.

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## ringtail

I'd say for $ 55 k  you would want half the ground floor built aswell. Prepping a slab aint rocket science and it doesnt take long to do a really good prep job, provided the excavator driver is good. You will need 20 sheets of reo, plus tench mesh,angles, ties, chairs, plastic etc...termite treatment for pennos. My neighbour just got a habitable slab poured under his raised house for $13 k plus the pump $ 500. The size was 110 sqm.

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## Cementer

If you can work out the volume of concrete needed, i.e 250m2 at 100mm is 25 cubic plus footings...
Work out total volume of crete and it will be very close to $800 per cubic for all works. However we work out pricing for these types of jobs, it always comes pretty close to the $800 per cubic mark for total price no matter how we work it out. e.g. If total cubic of concrete is say, 40 cubic then the total job would be around 32k.

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## lisachan25

The works included in the quotation are profile site and mark out, all the excavation, supply, laying, and finishing of the slab. So pretty much everything. Is 55k too much for all these work?
So I take it $800 per cubic is like the benchmark?

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## ringtail

You do have some variables that can blow the cost out. Earth moving is the biggest one. At $ 90 - 150 per hour if things go pear shaped it adds up quick. Dont forget that the concreters will be putting a good mark up on the earth works - as they are entitled to do. I'd be taking cementers advice as far as pricing goes. Make sure you get several ( 3 ) quotes and start asking questions if they vary by more than $ 2k.

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## lisachan25

Cool. Thanks guys for the all advices.  :Biggrin:

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## Kevin_Baker

Also make sure that you allow for the electrical/earth bonding to the reo that is required now!

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## Cementer

$800 is a good benchmark to work on. Excavation included in this is digging of the footings. Block cut and removal extra. So is piering.

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## lisachan25

My dad is an electrician so at least we get to save money there... :P
Btw, is yellow page the best place to look for professionals?

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## ringtail

I'd take a drive around your local area and look at building sites, ask the builder if he is happy with the concreter and get some phone numbers. Cold calling someone in the yellow pages is not as effective as saying " I got your name from such and such builder "

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## lisachan25

Cool, thanks for the advices

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## Marc

You don't embark in an expense like that on the basis of ONE quote, neither on the guesstimates of fellow forumites as much as they may be correct. 
You can work out the volume of concrete and multiply by $280 or you can ring up 5 concrecters and get 5 quote. Get rid of the cheapest and the highest, eliminate those who you can tell are shonky due to DNA baggage and you will be left with 2 or 3 to choose from.
Best of luck. Remember you will have to repay all that money and that $10,000 is about 6 month worth of repayments. It pays to do your homework. 
Kind Regards
Marc

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## jago

> You don't embark in an expense like that on the basis of ONE quote, neither on the guesstimates of fellow forumites as much as they may be correct. 
> You can work out the volume of concrete and multiply by $280 or you can ring up 5 concrecters and get 5 quote. Get rid of the cheapest and the highest, eliminate those who you can tell are shonky due to DNA baggage and you will be left with 2 or 3 to choose from.
> Best of luck. Remember you will have to repay all that money and that $10,000 is about 6 month worth of repayments. It pays to do your homework. 
> Kind Regards
> Marc

  
$280 m2 what is it Kryptonite...

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## Marc

Yes, no harm in a bit of fun.
However volume is usualy measured in m3 and not m2 which on a 100 mm slab makes it some 10 times cheaper. In fact I think that $280 a m3 is rather cheap for a slab if you include excavation.
If the initiator of this thread is interested in not overpaying his slab, the best he can do is get lots of quotes and discard the marginals.
Ah... and avoid Kryptonite of course!

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## jago

I was drunk when I put squared and not cubed ... 
Your right about getting more than one quote as the OP didn't give enough info for anybody to quote on from the forum... its all generic advice. 
OP if your dad is a tradie does he not contacts that he has worked with?

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## lisachan25

My dad knows a few builders, and he got a few names from them, don't think he knows any concrete contractor directly. And thanks for the advice Marc, we are looking to get more quote as well, but maybe after the Christmas period.

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## Concretecure

> Hi, we are looking to rebuild our house and I'm just wondering what kind of price I can expect for the concrete slab, which is about 250m2 with a depth of 600mm. I'm new to these stuffs so please tell me if more information is needed. Thanks.

     Hi there do you have a set of plans? if not it depends on whether it is a raft slab or a waffle slab.waffle slabs are a cheaper option but not always suited to the site or house design . There are some estimates which could guide you but always be prepared for unforseens. If i had some more accurate measurements i could give you an accurate price. ive only joined the forum today so discard this if it doesnt apply as we are six months further on than that now. just practicing replies and so on cheers

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