How to Cure Concrete in Hot Weather?
Above 35C concrete loses mix water fast and can lose 20% strength without curing. Keep slabs continuously damp for 7 days minimum (14 for columns and beams), start within 2 hours of finishing, and use ponding, wet hessian or curing compound. This is the highest-ROI week in any concrete job.
Step-by-Step Takeoff
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1
Start curing within 2 hours of final finish, sooner above 40C.
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2
Pond slabs 25-50 mm deep or cover with wet hessian; re-wet twice daily.
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3
Cure slabs 7 days, columns and beams 14 days.
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4
Use the calculator cure-time panel to plan loading: foot traffic at 24-48 hours, full cure 28 days.
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5
Never let the surface dry white in the first 72 hours.
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6
Wind breaks and sunshades cut evaporation as much as extra water does.
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7
Log morning and evening surface temperature; retard set with chilled mixing water past 40C.
Guide FAQ
How long to cure a slab?
7 days minimum; 28 days to full design strength.
Is curing compound enough?
Yes if applied at the specified coverage; ponding is more forgiving in extreme heat.
Can you pour concrete at 45C?
Yes with precautions: pour at night, chill water, wind breaks, and cure instantly.
Why did my slab surface dust?
Premature drying or over-troweling bled water back up โ both trace to missed curing.
When to remove formwork in heat?
Sides at 24 hours, soffits and props per span tables (often 14โ21 days).
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