You 'build-up' levels using crushed aggregate in layers, with each layer being not more than 150mm thick and thoroughly compacted before placing the next. I'd suggest using Type 1, 50mm crusher run or similar.
On 'critical pours' variation in concrete thickness can be a huge problem as it results in differential rates of hydration and curing, which can, in some cases lead to internal stresses, cracking and even slab failure. However, for a small residential project, as long as you have 100-150mm concrete thickness throughout, there shouldn't be a problem.
Concrete base - Concrete base
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Tony McC
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Mikey_C
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th concrete should be a consistent thickness over the entire slab area this gives it the freedom to move (trough expansion and contraction without cracking. If you are suggest that there will be a considerable amount of type 1 and the side of the concrete after the shuttering removal then, i guess you can then put more concrete into retain both concrete and type 1 or build a small retaining wall, if you are going to do the later you may wish to do it first.
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sako
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Hi.Because i have a slope where the concrete slab will be, the slab will be mostly above ground so i intend possible building up with hardcore to level it out and obviously reduce volume of concrete but i dont want to see hardcore when i take shuttering away so that is what i meant when i suggested sloping edges of hardcore so i have full depth of concrete round edges, would this be normal practice under these circumstances?
cheers sean.
I
cheers sean.
I