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?

#11

Post by Fintray »

Those of a nervous disposition should look away now! :D
nowty wrote: Sat Aug 20, 2022 12:35 pm Whichever way you do it I recommend a concrete truck or at least get stuff delivered. ;)

Reminds me of my own enforced concrete laying in difficult conditions. :evil:
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Incidentally where does that culvert lead to?
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Re: Does anyone have knowledge of laying concrete slabs?

#12

Post by nowty »

Fintray wrote: Sat Aug 20, 2022 2:17 pm Those of a nervous disposition should look away now! :D
Incidentally where does that culvert lead to?
[/quote]

It meanders part underground in a culvert and part overground in a ditch to a tidal part of a river.

Todays picture at the 10 year mark, I think my work will last quite a long time. :D
Image


But the scariest picture of all time was, :?
Don't do this at home folks as there were two "incidents", which I never fessed up to at the time. :oops:
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Re: Does anyone have knowledge of laying concrete slabs?

#13

Post by Oldgreybeard »

nowty wrote: Sat Aug 20, 2022 3:12 pm But the scariest picture of all time was, :?
Don't do this at home folks as there were two "incidents", which I never fessed up to at the time. :oops:
Image
That's the photo I very well remember from the other place, plasterboard props holding up shoring and looking seriously scary. IIRC Biff got quite concerned about that photo at the time.
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SafetyThird
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Re: Does anyone have knowledge of laying concrete slabs?

#14

Post by SafetyThird »

Thanks everyone, looks like scraping the hard clay to as close to flat as possible and then putting down the visqueen and going from there. I have some 4x8 that will be getting screwed between the upright posts so that will be heavy shuttering and will also act as a point to run a tamping bar against, I can get those nice and level and work off those.

I'll not be mixing the cement, I've done that before and, well, I'm happy to pay a nice man in a truck to deliver it for me. I'm also going to see if there's a local tradesperson with a concrete poker, float, etc that I could pay for an afternoon's work, I think that would be money well spent too. I'll get some reinforcing mesh and lay that on bricks and make the slab 150mm, it's only ever going to have a car or motorbike in there. The heaviest vehicles I own are an old Massey 135 tractor and a landcruiser, either of those might end up in there for repairs so a reinforced 6" slab should cope with everything I'm likely to throw at it.

I'll keep you all updated as I progress.

Oh and Nowty, I remember your epic concrete work from the other place, lovely to see it still holding up in such good condition, that was an amazing project.
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Re: Does anyone have knowledge of laying concrete slabs?

#15

Post by Fintray »

Oldgreybeard wrote: Sat Aug 20, 2022 3:28 pm
nowty wrote: Sat Aug 20, 2022 3:12 pm But the scariest picture of all time was, :?
Don't do this at home folks as there were two "incidents", which I never fessed up to at the time. :oops:
Image
That's the photo I very well remember from the other place, plasterboard props holding up shoring and looking seriously scary. IIRC Biff got quite concerned about that photo at the time.
Yes, that's the one where a lot of people were worried of it all ending badly, but now it's done and lasted these last ten years so by the looks of it it'll see Nowty out.
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Galahad
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Re: Does anyone have knowledge of laying concrete slabs?

#16

Post by Galahad »

nowty wrote: Sat Aug 20, 2022 3:12 pm Don't do this at home folks as there were two "incidents", which I never fessed up to at the time. :oops:
For God's sake don't tell us now. The nightmares will start up again. :D
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Re: Does anyone have knowledge of laying concrete slabs?

#17

Post by spread-tee »

nowty wrote: Sat Aug 20, 2022 3:12 pm
Fintray wrote: Sat Aug 20, 2022 2:17 pm Those of a nervous disposition should look away now! :D
Incidentally where does that culvert lead to?
It meanders part underground in a culvert and part overground in a ditch to a tidal part of a river.

Todays picture at the 10 year mark, I think my work will last quite a long time. :D
Image


But the scariest picture of all time was, :?
Don't do this at home folks as there were two "incidents", which I never fessed up to at the time. :oops:
Image
[/quote]


Jeez mate, that gave me some sleepless nights , we had done a 3.5M deep ground beam build over just before that and the shoring specified for it was , shall we say thought provoking? and then seeing your picture...........well I sh1t myself TBH.

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
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Re: Does anyone have knowledge of laying concrete slabs?

#18

Post by John_S »

Anyone have any thoughts about a crack control joint or two?
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Re: Does anyone have knowledge of laying concrete slabs?

#19

Post by AE-NMidlands »

I have always been impressed by the thin reinforced concrete skins used abroad (mainland Europe) where "we" seem to go for massively thick slabs. I'm sure that instead of 6 inch slabs it is smarter to use 2 or 3 inches with quite a thin steel grid in it.
Unless you actually want the thermal mass of course...
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Re: Does anyone have knowledge of laying concrete slabs?

#20

Post by SafetyThird »

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.
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