OT ConstructionConcrete & outdoor living

Can you pour concrete in winter? Yes, with the right preparation

The short answer: Yes. A winter pour works when the ground isn’t frozen, the mix is chosen for the temperature, and the concrete is protected until it has gained enough strength to survive a freeze. In western Washington, rain is often a bigger challenge than frost. Here’s how we handle both.

Winter pour protectionFresh concrete under insulating blankets and a rain tent, on a compacted base that is not frozen. 12345
Winter pour protection: keep it dry and keep it warm
  1. Tent or canopy keeps rain off the finish
  2. Insulated blankets hold heat while the concrete gains strength
  3. Fresh slab, protected until it reaches about 500 psi
  4. Compacted base that isn’t frozen
  5. Rain and cold are managed separately

What counts as cold weather for concrete

The industry reference, ACI 306, defines cold-weather concreting as conditions where the average daily air temperature stays below 40°F for three days or more and the air doesn’t rise above 50°F for more than half of any 24-hour period. Fall and spring days that don’t meet that definition can still bring frost, so the guidance also calls for protecting fresh concrete for the first 24 hours whenever a frost is forecast.

The number that matters most is 500 psi. Concrete that has reached about 500 psi, and has been protected from freezing until then, isn’t damaged by a single freeze. At around 50°F, well-proportioned concrete typically gets there in about two days. Colder concrete takes longer, which is why protection and temperature control are the heart of a winter pour.

What winter looks like here

Western Washington winters are more wet than frozen. Sea-Tac averages about 39 inches of precipitation a year, January lows average in the mid-30s°F, and the long-term record shows roughly 30 nights a year below freezing, with some recent winters seeing far fewer. Most winter pours here are about managing rain and cool temperatures, with an occasional cold snap that calls for serious freeze protection. We watch the forecast through the whole protection period, not just on pour day.

How we pour in winter, step by step

  1. Read the forecast, then decide. We look at the lows and highs for the pour and the days after it, not only the pour day. If a hard freeze, a storm, or flooding is on the way, we reschedule instead of gambling with your concrete.
  2. Prepare the ground. Concrete can’t go on frozen subgrade, snow, ice, or standing water. We clear and thaw the area, keep the base from freezing, and compact it before forms and reinforcement go in. Frozen ground that thaws later can settle and take the slab with it.
  3. Order the right mix. Cold-weather mixes are specified for the conditions: concrete delivered warm, typically around 50 to 65°F at placement depending on the thickness, a low water-to-cement ratio, and accelerating admixtures where they’re appropriate. Admixtures speed the set and lower the freezing point slightly, but they don’t replace protection.
  4. Pour and finish on the concrete’s schedule. Cold concrete sets more slowly than summer concrete. Finishing too early, while bleed water is still rising, can leave a weak, dusty surface, so we let the slab tell us when it’s ready instead of following the clock. We never add water to make finishing easier.
  5. Cover it right away. Insulated curing blankets go on as soon as the surface can take them, with edges and corners covered first because they lose heat fastest. The goal is to keep the concrete around 50°F until it has reached strength, and longer for structural work like walls and footings.
  6. Keep the rain off. Rain on a fresh surface can ruin the finish. When rain is forecast, we prop tents or canopies over the pour so the surface stays dry while it sets. This matters most on stamped, colored, and exposed-aggregate work.
  7. Add heat only when the weather calls for it. In a hard freeze we enclose the work and heat it, with vented or indirect heaters only. Fuel-burning heaters that exhaust into the enclosure release carbon dioxide that can carbonate the fresh surface and leave it soft, chalky, and dusty. Heating also lowers humidity, so we protect the surface from drying out too fast.
  8. Cure, then wind protection down gradually. Concrete has to hold on to its moisture to keep gaining strength, so we use blankets and curing compound rather than soaking it, since water curing in cold weather can reduce freeze-thaw resistance. When protection comes off, it comes off gradually, because a sudden temperature drop can cause thermal cracking.
  9. Go easy in the first winter. Keep de-icing salts off new concrete during its first winter, and follow our guidance on when to walk and drive on it. Cold weather means longer waits than summer.

The case for a winter pour

  • Easier scheduling. Winter is often the quietest season for concrete contractors, which can mean quicker scheduling and a finished project when spring yard season starts.
  • A slower cure can be a stronger one. ACI notes that properly protected concrete placed in cold weather can develop higher ultimate strength and greater durability than concrete placed at higher temperatures, and it’s less prone to thermal cracking.
  • Gentler drying conditions. Cool, humid weather means less rapid surface drying than a hot, windy summer day.
  • Wet weather shows the real problems. Drainage, French drain, and waterproofing work is easier to plan in the rainy season, because you can see where the water collects and runs.

When we say wait

Winter pouring isn’t a free-for-all. We’ll recommend waiting when the ground is frozen and can’t be thawed, when a hard freeze is forecast that we can’t protect against, or when heavy rain, flooding, or snow would compromise the base or the finish. A short delay costs far less than replacing a slab.

Questions to ask any contractor about a winter pour

  • How will you keep the concrete from freezing until it reaches strength?
  • What will the concrete temperature be at placement?
  • What mix and admixtures will you use, and why?
  • How will you keep rain off the finish?
  • If you use heaters, what kind, and how are they vented?
  • How long will protection stay on, and how will you remove it?
  • When can we walk on it, drive on it, and use de-icer?

Common questions

Is concrete poured in winter weaker?

Not when it’s protected. The danger is freezing before the concrete has gained enough strength, not cold itself. With the right mix and protection, winter concrete can reach full strength, and slow curing can even raise its ultimate strength.

Does a winter pour cost more?

Cold-weather protection takes extra materials and labor, and we account for it in your quote so there are no surprises.

How long until I can use a winter-poured slab?

Longer than in summer. Cold slows strength gain, so we give you dates based on the actual temperatures after the pour.

Can you pour concrete in the rain?

Light rain can be managed with tents and canopies over the work. Heavy rain, standing water, or flooding can compromise the base and the finish, and we’ll reschedule if conditions are against it.

Concrete work we do year-round

Sources

This guide is general information for homeowners, not engineering advice. Requirements for structural concrete and for your specific site can differ. Last updated October 2026.

Planning a pour this winter?

Call or email us. We’ll check the forecast, the ground, and the schedule with you.

Call 206-483-5334
Get a quote
Call 206-483-5334Get a quote