Can You Boulder In The Rain or When The Rock Is Wet?

I was wondering if it is ok to go bouldering in the rain or while the rock is wet so I did some research. 

Is it ok to climb in the rain or when the rock is wet? Bouldering in the rain isn’t recommended because some rock types such as sandstone are more likely to break off and thus ruin the route when it is wet or raining. As for climbing on wet rock, for preserving the rock face and for safety purposes, the general rule of thumb is not to. 

Many climbers go on trips or travel great distances to try the routes and don’t want the unexpected weather to prevent them from bouldering. But blanket statements about the type of rocks can be misleading or unrelated to the route you are looking at so it is important to get as much information as you can.

What Rock Is OK To Boulder While Wet?

As mentioned above, the type of rock can highly affect whether or not it is safe to boulder while wet. Some climbers say it is unethical to climb any type of rock while it is wet so keep that in mind. However, bouldering is much less damaging to the rock face than rope climbing so it is still worth considering the different rock types in your decision.


Generally, sandstone is dangerous to climb when wet due to water making sandstone weaker. In addition, you are more likely to break handholds/footholds when sandstone is wet so you should avoid it as much as possible. However, not all sandstone is the same. A good way to learn what is applicable for the area you are in is to ask the locals.

  • Fountain sandstone around Boulder IS generally safe to boulder while wet.
  • Nutall sandstone at the New IS generally safe to boulder while wet.
  • Navajo sandstone is NOT safe to boulder while wet.
  • Wingate sandstone found in the desert southwest is NOT safe to boulder while wet.


Granite is generally the safest to climb while wet. This is mostly because it is very strong, not very porous and dries quickly. However, there is always a risk of water damage in cracks that you can’t see in different levels of the rock so it is important to evaluate the rock face before bouldering and while you boulder.

Some locations, such as Leavenworth in Forestlands have reported small breaks in the granite hours after climbing but it is unknown if the rain was the cause.


Limestone is generally strong and is less likely to break than sandstone while wet, however, many climbers have reported that limestone is more slippery when wet and thus any “polished” handholds or footholds will be more difficult to climb and more dangerous.

One thing you can do is evaluate the holds before you start climbing and also clean your shoes before you start climbing so there isn’t any additional dust or mud that would make the climb more slippery than it already is.

If you are new to bouldering, I’d recommend waiting till it dries before climbing routes in an area you’ve never been to.

How Long Does Rock Take To Dry?

Generally, it takes about 24 hours after rainfall before the rock is completely dry. Of course, some rocks take less than an hour to dry and some take a few days. This is also dependent on the environment that the rock is in so it is also location dependent.

Below are a few of the most common factors to consider when evaluating how long it takes the rock you are interested in drying.

Rock Type

Of course, if the rock is more porous, it will take longer to dry than if it is non-porous such as granite. There are many reasons for this, but a big reason is that the rain can penetrate deeper into the rock face if it is more porous and the deeper it penetrates, the longer it takes to dry. Because of this, not all rock requires as much time between rainfall and when it is dry.

  • Sandstone: Sandstone, depending on where the sandstone is and what kind of sandstone it is, can take up to a few days to dry. For example, some red sandstone can take up to three days to completely dry, whereas some sandstone common in the Fountain CO area only takes a few hours to dry.
  • Granite: Generally, granite dries quickly. This is likely because it isn’t very porous and thus water doesn’t penetrate the layer of rock as much
  • Limestone takes more time to dry than granite and generally less time to dry than sandstone.


Generally, if the temperature outside is hot, it will dry faster than if the temperature was cold. Heat changes the evaporation rate of water and thus, changes the time it takes to dry rock.

If it is particularly cold, the water may not evaporate at all and it may freeze on the rock instead. Whereas, in an incredibly hot area, the water may evaporate moments after it touches the rock face.

Heat should be considered at all stages of the rock getting wet – before, during and after it gets wet. The warmer it is at each of these stages, the faster it will dry.


Not surprisingly, the humidity in the area will also change the rate at which the rock will dry. In some desert areas, humidity is well below 10% before and after a rains storm. Whereas some more humid areas may range far above 30% before and after a rainstorm.

If there is more humidity, it will take longer for the rock to dry because there is already a lot of water in the air and thus, it is harder for the water on the rock to evaporate.

How To Evaluate If Your Route Is OK To Boulder When Wet?

If you are on a quick weekend trip or have flown half-way across the world only to have unexpected rainfall every day, you may be considering bouldering, despite the risk outlined above.

In that case, you may be tempted to go to where the route is to evaluate the risk involved yourself, just in case you could boulder without a problem.

Local Weather Warnings

Depending on the area that you want to boulder, there may be local weather warnings. For example, in many spots in Zion National Park, there are flash flood warnings almost every time it rains in certain seasons. In addition, people die every year because they ignore the flash flood warnings.

Weather warnings should not be ignored and if there are local weather warnings, try and find alternative locations to boulder. You can often drive an hour in one direction and find completely different weather.

The Approach

In addition to the climb itself, you should consider the safety of your approach. If you are in a mudslide prone area, the approach can be incredibly dangerous and thus you should avoid it. To learn if there are frequent mudslides, you can usually just do a quick online search for ‘mudslides in (location)’ and if a lot comes up, then it is probably a more mudslide-prone location.

There are, of course, many places where the approach is likely safe and already dry so use your best judgment.

Rock Type

The beat of this drum may seem over-played in this article, but that is because it is one of the biggest concerns that many boulders have when considering whether or not they can boulder while it is wet.

If the rock is more porous, it will likely be riskier to climb. Not only does erosion add to the mix, but some rock, such as sandstone is weaker when it is wet.

See above for the safety of climbing on each rock type.


Cracks in the bouldering route, though necessary to do a clean climb, is also an indication of weaknesses in the rock face. Generally, the more cracks in the rock or the wider they get makes the rock weaker.

While rock is wet, erosion is not only working on the outside of the rock-face, it is also working on every crack and crevice that is also on the rock. 

Evaluate each crack to see if it is ok to hold your weight along with any movement you may cause it while bouldering. If there is any movement in the crack, stop climbing – the risk isn’t worth it. Not only could you break the rock face and ruin the experience for other climbers, but that rock could break on you or smush you, etc.


Certain rock types, like sandstone and limestone, are more slippery when wet. This isn’t an indication of the sturdiness of the rock as it is that you may slip more often and hurt yourself. 

Consider that all falls are ground falls and some falls are more dangerous than others, despite how fat or wide your crash pad is.

Early in my climbing experience, I was sport climbing outdoors and it started to unexpectedly snow. I continued to climb despite the cold and wet. Unfortunately, along with my frozen toes, the rock became very slippery. I took a hard fall and bruised my knee badly. I could hardly walk without constant pain for over a week after that and it took weeks to heal. Not worth it. (Sid-note, I was young and dumb, hopefully, I’ve gotten a little smarter since then…)

Hold Stability

If you get to the point that you decide to start evaluating individual holds, consider feeling whether or not the holds feel stable before you start the route. 

If you feel a few holds and they seem fine so you decide to keep climbing, constantly evaluate each hold that you use. 

 If there is any indication that the hold may break, consider bouldering elsewhere. As mentioned many times in this article, a part of the rock face breaking not only ruins the route for other boulderers, it also may cause injury to you.

Climbers Ethical Arguments And Wet Rock Bouldering

Climbing on wet rock is a popular and often passionate discussion among climbers. Most ethical arguments are related to trad and sport climbing gear ruing the rock face, but there are also a lot of concerns for the integrity of handholds and footholds on the route, which are related to bouldering as well.

Climbing Erosion Ruins Rocks

This is probably the most popular argument among climbers that feel you should avoid the climbing wet rock. The idea is that climbing erosion (erosion caused by climbing) is more damaging when the rock is wet compared to when the rock is dry.

A common rebuttal is that climbing erosion will eventually ruin the rock face, even if climbers only climb when it is dry and thus, climbers shouldn’t feel pressure not to climb when the rock is wet. 

Some Areas Rain Daily

This argument comes up frequently for climbers that live in areas that rain often and feel they should be able to climb despite the rain. The idea is that there wouldn’t be any climbing in those areas if they had to wait for the rock to dry and thus there is no point in not climbing when it is wet.

There aren’t common rebuttals to this argument.

Where is the best place to boulder after it rains?

Bouldering indoors at a local gym is the best place to boulder after it rains. Not only do you negate any safety or rock face integrity concerns, but you are likely to meet boulders in your area that would be great climbing partners when the rock dries.

Of course, not everywhere has a local gym (one of my favorite places to boulder is in St. George Utah and they don’t have a climbing gym, yet…). In which case, there isn’t the best place to boulder after it rains unless your willing to travel to a gym.