Concrete Curing Temperature Guide

Concrete gains strength through a chemical reaction that depends on temperature. Ideal ranges and precautions for pouring in cold and hot weather.

Concrete temperature guide

Condition	Temperature	What to do
Ideal curing	50–75 °F (10–24 °C)	Keep moist for at least 7 days
Cold weather (ACI)	Below 40 °F (4 °C)	Use blankets, heated enclosures, accelerators
Freezing risk	Below 32 °F (0 °C)	Must not freeze before reaching ~500 psi
Hot weather	Above 90 °F (32 °C)	Pour early, use cool water, retarders, keep damp
Concrete at placement	50–90 °F (10–32 °C)	Check with a concrete thermometer

Notes

Strength development slows sharply below 50 °F (10 °C) and nearly stops near freezing. If fresh concrete freezes before reaching about 500 psi (3.5 MPa), ice crystals can permanently weaken it. In hot weather, water evaporates too quickly, causing plastic shrinkage cracks and lower strength. Concrete typically reaches about 70% of its design strength in 7 days and full strength at 28 days under normal curing.

Frequently asked questions

How cold is too cold to pour concrete?

Take cold-weather precautions below 40 °F (4 °C); don’t let it freeze while curing.

Can concrete cure in cold weather?

Yes, with insulation blankets, heated enclosures or accelerating admixtures.

How long does concrete take to cure?

It can be walked on in 24–48 hours, driven on after about 7 days and reaches full strength at 28 days.

What happens if concrete freezes?

Early freezing can cause scaling, cracking and permanent strength loss.