It's just good that it rains on freshly poured concrete?

[BORNER]

Yesterday we poured a wall with coarse concrete in a form that was ready by lunchtime, then sprayed a fine mist of water over the concrete surface and covered it with plastic, after which the entire form was covered with a tarpaulin.

Today it has started to rain and it is expected to continue for a few days according to SMHI. Is it perhaps good to remove the tarpaulin and let it rain on the concrete, which has now been curing for about 20 hours? Or is there any disadvantage to letting the concrete and form get rainwater on them for several consecutive days?

 

[Cruzze]

Light rain is fine, but you should avoid running water on the concrete before it has fully set to prevent leaching out the binder (lime). Keeping the plastic on is my advice.

 

[BORNER]

Thank you @Cruzze for the quick response! But you still need to spray some water now and then, right, or is the high humidity and low temperature enough to prevent the concrete from drying out too quickly?

 

[Cruzze]

Thanks @Cruzze for the quick response! But you still need to spray a little water now and then, or does the high humidity and low temperature suffice for the concrete not to dry out too quickly?

Exactly. You can lift the plastic now and then and top up if needed. It's not rocket science.