Can Concrete Be Poured In Rain? | Find out

Concrete cannot be poured during heavy rain, but you can pour it after or before the rain as possible.

Concrete pouring must be avoided during the rain as it can bring many challenges and problems. Also, fresh concrete must be covered with plastic as fast as possible because it may then cure in the bag itself.

The biggest issues you may face while pouring concrete in the rain are bleeding, weak surface finishing, strength gaining, and concrete laitance.

Pouring concrete during the rain is possible, but it may compromise the strength and raise the tendency to dust and scale. Hence here, we will be discussing pouring concrete surfaces during, before, and after rain with its effects.

Can You Pour Concrete In Rain? If So, How?

You can pour concrete in the rain but avoid heavy rain weather. Heavy rain may wash out some cement from the surface, leading to inappropriate surfacing with cracks or other issues.

But if you have any deadline to complete the project, you are required to take some precautions and tips to handle pouring concrete on rainy days –

Don’t Let Rainwater Stay Under Concrete Pour

Do not work or pour concrete over rainwater. Clear the collected rainwater from the surface and let the surface be free of Excess water.

Make sure to check the surface that you are going to pour concrete is dry before starting. Never make the mistake of pouring concrete onto wet surfaces or water-filled cavities from where you can not let water displace or escape.

Plan Ahead Of Time By Checking The Weather

Checking the weather forecast of the day you decided to pour is essential for rainy days. If rain is in the forecast, plan your schedule accordingly. Also, ensure to have a plastic sheet or any waterproofing materials ready to cover the worksite.

Use Less Water In The Concrete Mix During Rainy Days

If you are storing aggregates outside, rainwater will make your crushed stones and sand wet. It will automatically add additional water to your concrete mixture; hence, use less water while making a concrete batch.

Also, keep an eye on your cement and ensure that no moisture gets into the bags wherever you store them. You must store cement in a dry environment as the water may get mixed with cement and can set or cure it faster than you realize.

Stop Pouring If It Starts Raining

Suppose it starts raining while concrete is pouring, do not panic. All you need to do is wait until the rain passes, then pull or push water off the surface’s edge before finishing.

Dry The Surface

A large amount of standing water on the top of newly poured concrete can leech cement and produce more issues that may damage the end product. Ensure to brush off surface water before covering.

Check And Install Good Drainage

Good drainage will ensure no rainwater pools in trenches dug for slabs, driveways, or footings. So, it is vital to ensure good drainage because rainwater can also bring contaminants. There will not be any issues pouring concrete in the rain unless water drains away.

Perform Proper Inspections After Raining

Once the rain has passed, inspect the concrete and find out the damage or water pools on the surface, if any. Perform a simple scratch test to determine whether the concrete surface has any adverse rain impact.

Suppose you find any harm or dimples on the surface left by rain, contact experts. They will use float to remove excess water pools and smoothen the concrete surface immediately.

Waterproofing Covers

When you pour concrete in the rainy season, make sure you have waterproof covers or tarpaulins that cover the entire area. Keep them on standby as each site is ready to get a cure.

Be Ready With The Correct Types Of Materials And Equipments

Confirming the success of the concrete pouring during rainy days is done by its preparation. Thus, be ready with the suitable materials and equipment in hand to deal with the heavy rain, wind, and water.

Keep A Check On the Temperature

Keep an eye on the temperature because concrete may lead to cracks or get uneven during cold weather. If the temperature lowers and gets down more in the rainy season, you can see damage in the poured concrete, so be ready with the additional heated enclosure.

Can You Pour Concrete After Or Before Rain?

You can pour concrete before or after raining without any stress. There are many solutions to protect the concrete poured before or after rain.

If you pour concrete before the rain, you need to check the weather forecast and get ready for the heavy rain. Cover the poured concrete with plastic or waterproof covers and materials so that your freshly laid surface may stay rain-free for at least 6 to 8 hours. After eight hours of the concrete pouring process, there will be the minimal effect of rain.

If you pour concrete after rain, ensure to clean the surface and get rid of the water pools. You only have to be prepared for the rain occurring later and clear the surface on which you will pour concrete. Let the surface dry first. Again, check the tips and precautions discussed in the above section to ensure the proper pouring of concrete.

Also, keep in mind after rainy days, there comes the cold season. Cold temperature may also lead to some damage. Thus, be prepared accordingly.

How Rain Impacts Concrete Pouring?

The effects of rainwater depend on the curing stage it reaches before rain occurs. If you have poured concrete already and it has passed about 5 to 6 hours, its effect will be minimal. But if rain occurs after pouring concrete immediately or in a short time, then it may lead to some damaging effects –

  • Rain falling on the freshly poured concrete may harm the entire surface and the float/ level finishing.
  • If extra water makes its way to the concrete mix, the result will get worse. It can lead to weak concrete overall.
  • Washing of concrete may also occur if there is heavy rain, resulting in uneven bumps on the surface.
  • Before pouring footings, driveways, or slabs, rain may have a detrimental effect if the subgrade is oversaturated. It may result in ponding because the extra water gets absorbed by fresh concrete, which automatically changes the ratio of water-cement.
  • Rain may also wreak havoc on freshly poured and sealed concrete that may cause the sealer to blister and bubble. (Tip: Ensure to apply sealer when it can stay rain-free for 24 hours after sealing.

Hence, for this reason, it is crucial to check out the weather forecast before pouring concrete in the rainy season. Also, ensure to follow some tips and take precautions beforehand.

Frequently Asked Questions

1. How Long Does Concrete Take To Cure Before Rain?

If the concrete pouring has passed around six to eight hours, rainwater may have little to no damage. Besides, once concrete sets, water walls act as a beneficiary to aid curing and hydration.

2. How To Check Whether Rain Has Caused Damage to Concrete?

Perform a simple scratch test. Also, inspect the entire surface and find any water pool or other damage.

3. Can You Pour Concrete On The Wet Ground?

You need to let it dry or cover the wet ground with the tarp before pouring to prevent water on the ground. Wet ground is not a good base for the fresh concrete pouring.

4. What Happens If It Rains After 2 Hours Of Concrete Poured?

There might be some damages such as water pools, decreasing strength, and uneven bumps. And if it gets the space to enter the concrete mix surface in-depth, you will find the cracks, bents, or other problems within a short time.

5. What Is The Best Time To Pour Concrete?

The perfect time to pour concrete depends on the area you live. The temperature must be between 50 to 60 degrees Fahrenheit for most of the day. According to your area, the season can be spring, winter, or fall.
Note: Remember that the best time to pour concrete is during the moderate months of the year.