# Forum Home Renovation Concreting  laying a large concrete slab

## jumpstart26

Hi all, im looking a pouring a 10metre x 10 metre slab. have all the ground work, form work etc done..was planning to do it 3 x 10 metre strips as I only have a 3 metre straight edge but can anyone tell me how would the pro's pour it all in one go? surely they wouldnt have a 10 metre straight edge??

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## Master Splinter

They will typically establish a few reference points a screed length apart (a blob of cement or a long nail stuck into the ground) before starting the main pour, and they will level off these. 
And you might find 30 square meters of concrete a rather large job for one (inexperienced) person - remember, you've only got about 45 minutes before the concrete starts loosing its workability.

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## Pulpo

Reference points, often using laser. 
Never easy. 
30m squares metres is not small for one with little experience. 
Just have plenty of help available. 
I'm getting this size done $700 for labour, a good price I hope a good job. 
If a house slab may consider but house slab no interest. 
Good Luck 
Pulpo

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## totoblue

I don't want to rain on your parade but have you worked out the size of this job? 
10 x 10 x say 100 mm is 10 cubic metres of concrete.  I presume you are not using premix bags but for the sake of calculation it is useful to know there are 108 x 20 kg bags per cubic metre [1].  So that is nearly 22 tonnes of dry material plus the weight of the water, at a guess another 7 tonnes. 
Even if you are getting it premixed from a concrete truck, do you have to wheelbarrow the concrete to the site?  Hope you are young and fit and have lots of mates (don't open the beer until after the concreting is done  :Smilie:  ). 
References
[1] Blue Circle Southern Cement - Easy Estimator

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## Terrian

> Hi all, im looking a pouring a 10metre x 10 metre slab. have all the ground work, form work etc done..was planning to do it 3 x 10 metre strips as I only have a 3 metre straight edge but can anyone tell me how would the pro's pour it all in one go? surely they wouldnt have a 10 metre straight edge??

  nope no 10m screed, as others have said, reference points, 1" x 1" stakes in the ground.
for a  9m x 7m I did, 4 of us, 2 on barrows, one on shovel (to spread) and me on 3.6m screed. We use f82 (I think it was) reo 
for 3m width you will want a 3.6m screed, not a 3.6m length of timber either, the timber will bow, wet concrete is heavy.

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## Terrian

> And you might find 30 square meters of concrete a rather large job for one (inexperienced) person - remember, you've only got about 45 minutes before the concrete starts loosing its workability.

   

> Reference points, often using laser.
> 30m squares metres is not small for one with little experience.

  30 m2 isin't really all that bad *if* you can get the concrete truck to spread the pour, these days I usually do 2.4m x 6m slabs as the biggest if I am the only one doing the work, with the concrete at about 75 - 80 slump, about 20 minutes of hard yakka.

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## looseless

Call in your mates.  Many hands make light work.  Have a barbie and plenty of beers...............afterwards. 
Find a mate who is experienced at screeding.  He is worth plenty of extra beer. :brava:

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## Terrian

^^^ best advice so far  :Smilie:

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## jumpstart26

thanks guys for the replies. all good advise..definately not doing it on my own..should have 4 or 5 of us working as concrete trucks wait for no one. Had thought of using stakes or metal pins to mark out the levels and that but thought there might have been some other "magical" way the pro's do it :Sneaktongue:

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## cherub65

> Hi all, im looking a pouring a 10metre x 10 metre slab. have all the ground work, form work etc done..was planning to do it 3 x 10 metre strips as I only have a 3 metre straight edge but can anyone tell me how would the pro's pour it all in one go? surely they wouldnt have a 10 metre straight edge??

  Depending on the slab use is this link will provide you an alternative to formwork, You can set this up and screed to. Leaving in place. Connolly Key Joint - Concrete Control Joints

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## wmhc

Heres a simple trick. 
You will need 3 people. 
Using the barchairs (reo supports).
Sitting a barchair on each side of the formwork run a stringline accross the top of both chairs. (make sure its tight) with a 3rd bar chair put your height in so that the top of the chair is level with the string line. 
Bear in mind that you want to make sure your formwork is right. 
A lazer level is worth its weight in gold. 
Regards

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