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How Long Does Grout Take To Dry?

How Long Does Grout Take To Dry?

Applying grout can take a lot of time and skill – but how long does grout take to dry once it has been applied?

Grout typically takes between 24 and 72 hours to completely dry. Of course, the exact time is going to depend on a few factors.

Factors that Affect Grout Drying Time

There are a number of factors that will change the amount of time it will take for grout to dry. Some of these factors include:

Type of grout

The type of grout you use will change how long it needs to dry before it is completely cured. Grout often consists of water, cement, and sometimes sand. Standard cement grout usually takes the longest needing between 24 and 72 hours to cure.

The reason cementitious grout takes so long to dry is that it requires being mixed with water before it is applied because it is made with a water-retentive additive which prevents it from absorbing too much moisture.

Epoxy grouts dry in a shorter amount of time since they don’t need to be sealed.

Epoxy grout is more difficult to apply but once it is cured, it is incredibly resistant and holds up well to weather changes and to stains. Since it doesn’t have the moisture additive like cementitious grout does, it does not need to be sealed.

Whether the grout is sanded or un-sanded will also change the drying time needed. Furan grout that contains fortified alcohol polymers will take about 24 hours to dry. Urethane grout will require a full week to cure.

Humidity levels

The higher the humidity levels, the longer grout will take to cure.

Waiting for grout to dry in a bathroom, for instance, will take longer than grout drying in a kitchen. After installing bathroom tiles, wait at least 2 or 3 days before sealing it. Of course, wait for the sealant to completely dry before using it in a shower.

Sometimes the culprit causing humidity levels to change is found in the unexpected.

One aspect that affects humidity levels is whether there are houseplants in the room. Indoor plants, such as lily or philodendron, tend to release moisture which raises the humidity levels in the room.

Seasonal changes also affect the amount of humidity in the air – a key problem that hardwood floors are forced to deal with.

Temperatures

For best results, install grout when the temperatures are between 50 degrees F to 100 degrees F, 10 to 37 degrees Celsius. Grout typically dries faster when the temperatures are hot. It takes more time to dry when the temperatures are cold.

The indoor or outdoor temperatures are not the only temperatures that matter. The amount of time grout will take to cure will also depend on the temperatures of the water and the powder mix. Hot water and powder grout cure faster than cold ones.

However, the hotter the temperature of the grout, the time you have to work with it before it dries will also be a lot shorter.

Where the grout is used, indoors or outdoors

It will generally take longer for grout to dry when it is installed outdoors.

The reason for this is that it is easier to control indoor temperatures using the HVAC system. However, the outdoor temperatures are affected by changing humidity levels that come with weather such as rain, or snow, and temperatures that cannot be easily controlled and may be colder than indoors.

Grout that is used indoors can take about a day to dry. Whereas, grout used outdoors can take up to 7 days, even in the best weather conditions, to dry.

Problems When Grout Doesn’t Dry

If grout is not allowed to thoroughly dry before using it, a lot of problems can arise. Some of the problems that happen when grout does not set completely include:

  • Weak joints
  • Cracking
  • Mold or mildew forming

Making It Dry Faster

The best thing to do is allow grout to dry naturally. Doing so could cause the grout to weaken, crack, loosen, and fall off.

Never use a hairdryer to speed up the drying process, since it will make the grout dry too fast and cause it to crack. Additionally, the heat from the hairdryer will only dry the top surface of the grout while the inside will remain uncured. While grout is curing, it goes through a chemical reaction that takes time.

There is very little you can do to make the grout dry faster without disrupting the curing process. However, there are several things to consider to make sure the grout is installed in the best possible conditions to allow it to dry as quickly as possible.

  • Before using grout outdoors, be sure to check the weather forecast. Make sure to check the minimum temperature for the next week is 50 degrees F, 10 degrees Celsius, or higher.
  • After applying grout outside, cover the area to protect it from extreme weather conditions.
  • Reduce the humidity levels indoors by turning on the air conditioning, or using a dehumidifier or fan. Also, remove any indoor plants that could give off moisture.
  • Use a grout that dries faster.

Sealing Grout

After the grout has completely dried, the grout will need to be sealed. Allow at least 48 to 72 hours for the grout to dry and cure before sealing it. The sealant should take at least 24 hours to cure. Some types of sealant take as long as 48 hours.

Final Thoughts

It’s very important to make sure grout completely dries or cures, before sealing it. This process should never be rushed. Generally speaking, grout takes at least 24 hours to dry. Of course, humidity levels and other factors will affect the drying time.

When it comes to allowing the grout to properly and thoroughly dry, always err on the side of caution, allowing more time is better than rushing the process.