Does anyone have knowledge of laying concrete slabs?

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Fintray
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Re: Does anyone have knowledge of laying concrete slabs?

#21

Post by Fintray »

SafetyThird wrote: Tue Aug 23, 2022 12:26 pm
spread-tee wrote: Sat Aug 20, 2022 8:19 pm Anyway, concrete, as others have said get it delivered by mixamate or someone, it will be pretty cost effective and much more consistent and with a couple of helpers you will get it laid in a couple of hours max. If you have never used a power float don't bother, they are not for the faint-hearted , hire a bull-float, then all you have to do is walk backwards and forwards and twist the handle and you will get a pretty good finish. As others have said set up the form and make sure it is really solid and level and you are good to go when the truck turns up, I would also put some fabric in as it is pretty cheap and wont do any harm, try to stand it a third of the way up through the thickness of the slab on bits of brick or tile or whatever you have to hand.

Desp
Thanks for that, I'll leave the power float and just go for the bull float instead. Have also seen a portascreed which might make getting the initial level a lot easier over the area. have a couple of people who can help me on the day. Now to get everything shuttered and set up. Will post more info once that's done in a couple of weeks.
You can also get the driver to make it a bit wetter so it flows easier and will help it to self level rather than lots of raking to get a level.
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djh
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Re: Does anyone have knowledge of laying concrete slabs?

#22

Post by djh »

FWIW, on the clay where we are there's a risk of heave so there's a big hole with some hardcore in (800 mm I think) and then a concrete raft on top 175 mm deep with a 450 mm ring beam round the edge, all reinforced of course. So check what conditions are like where you are. Also note that building regs come in at 30 m² if I remember correctly.

The depth under the garage is fairly restrained. The hole for the house is 2 m deep at one end and 1.5 m at the other. :shock:
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SafetyThird
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Re: Does anyone have knowledge of laying concrete slabs?

#23

Post by SafetyThird »

Put the slab in yesterday.

Concrete was late arriving but I got it floated reasonably. Read that you don’t finish it until the water reabsorbs which it hadn’t at bedtime. Should have stayed up late as by this morning it was solid.

There’s a few ripples where I didn’t get the float quite right, first time using it but I’ll take those off with a grinder before I paint it. All in all, much better than a dirt floor.


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Re: Does anyone have knowledge of laying concrete slabs?

#24

Post by Joeboy »

SafetyThird wrote: Wed Sep 28, 2022 9:41 pm Put the slab in yesterday.

Concrete was late arriving but I got it floated reasonably. Read that you don’t finish it until the water reabsorbs which it hadn’t at bedtime. Should have stayed up late as by this morning it was solid.

There’s a few ripples where I didn’t get the float quite right, first time using it but I’ll take those off with a grinder before I paint it. All in all, much better than a dirt floor.


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nowty
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Re: Does anyone have knowledge of laying concrete slabs?

#25

Post by nowty »

SafetyThird wrote: Wed Sep 28, 2022 9:41 pm Put the slab in yesterday.

Concrete was late arriving but I got it floated reasonably.

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Lovely job, bet your glad you had it delivered. :D
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SafetyThird
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Re: Does anyone have knowledge of laying concrete slabs?

#26

Post by SafetyThird »

Most definitely glad I had it delivered, would have taken several days to do that in a mixer, they loaded 6cum instead of 5 so it's a little thicker than originally planned but that's no bad thing.

Found that I could scrape off the ripples with a sharp spade so it's flat enough now, not perfect but it's a garage floor after all and only the 2nd slab I've ever poured, you learn a bit each time, don't you. Given it a run over with a broom to take the top powdery layer off and now just have to wait a couple of months before I can paint it, probably with epoxy floor paint, and then I can start putting stuff on it.

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