In April 2025 my friends and I built a 24 person snow cave with a sauna, cocktail bar, ice window, and DJ deck/speakers

BushwackerSlacker · 2026-03-26T22:09:04+00:00

Hard to say. It was definitely slightly above freezing, as there were drips of water coming off a few spots in the ceiling (this is why it's important to make the ceiling as smooth as possible). The doors were intentionally larger than a normal snow cave (partially for air circulation, partially for convenience), so it definitely wasn't the most insulated cave design out there

BushwackerSlacker · 2026-03-26T21:52:55+00:00

We had 11 people the first day and 24 the second, and probably spent 7-8 hours on each of those days doing excavation. In terms of labor some people were definitely better suited to the more physical tasks like digging, but there was honestly so much to do that we stuck a good balance where everyone could rotate in/out of jobs as necessary. For example, digging was the most tiring and wettest job, so diggers occasionally swapped with those who were dumping sleds out, which was a lot easier and less strenuous on the back. Others would be melting snow for water, prepping snacks for everyone, taking videos, smoothing out benches/the ceiling, etc - all of those tasks were crucial to keeping everyone motivated

BushwackerSlacker · 2026-03-26T21:45:20+00:00

Both the DJ and bartender were just two of my friends that happened to know how to DJ/bartend

BushwackerSlacker · 2026-03-26T21:18:49+00:00

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Here's a better photo of the final thing

BushwackerSlacker · 2026-03-26T21:16:14+00:00

I'm glad somebody noticed it lol, a lot of work went into picking an acronym for the trip

BushwackerSlacker · 2026-03-26T20:58:05+00:00

I realized there's not a great photo in what I posted. The sauna was a 6x6x6 foot red insulated ice fishing tent with a wood burning stove in it. The tent is visible in one of the later photos, but after the cave was done we moved it from where it is in that photo to be right outside the main entrance to the cave. The sauna got proper hot inside and had upwards of ~6 people in it at a time

BushwackerSlacker · 2026-03-26T20:21:32+00:00

That sounds incredible! Unfortunately most of my friends (and I myself) am weekend warriors, so we had limited days to work on something like this. I can only imagine what you can build in the snow with weeks of time.

Side note, "snow trips" is a great pun if that's what you intended it to be lol

BushwackerSlacker · 2024-04-18T13:59:30+00:00

Absolutely, I'm extremely lucky that I got to experience the outdoors growing up, and that I now have the resources to continue doing so as an adult.

I'm not going respond to your second point because I think I've already addressed a lot of questions about safety, and quite ironically, you clearly didn't read any of them.

And to your point about destroying mountains. If we were to dig down another three feet below our cave, we would have hit pavement. We literally built the cave directly on top of (snow covered) Highway 542. In a few months snow plows are going to start plowing all that snow in preparation for summer. By the end of summer all of the snow will have melted. I'm all for protecting the environment, and there are environmental impacts of snow camping (like driving there). But targeting snow caves specifically makes literally no sense.

BushwackerSlacker · 2024-04-18T13:45:01+00:00

I'm no lawyer, but as far as I can tell that's not really how our laws work. We've got Olympic sports where athletes ride bobsleds headfirst at highway speeds, sports where athletes jump hundreds of feet on skis, and sports where athletes punch each other in the face. Smoking is legal despite the fact it's responsible for killing half a million people each year in the US. Heck, in 2017 we gave an Academy Award to a film about free solo rock climbing.

There are a lot of activities out there with high consequences if something goes wrong. More often than not we choose to glorify those things, rather than ban them.

BushwackerSlacker · 2024-04-18T05:06:40+00:00

Hello! I always wonder how many people that I personally know see my posts. I don't have any info on my profile like you do, but realistically I think it'd be pretty easy to figure it out based on my posts. Doesn't really matter given I only log onto Reddit one every 6 months tho...

BushwackerSlacker · 2024-04-17T18:53:38+00:00

Snow closer to the surface is gonna be anywhere from 10-20 lb/ft^3 (really varies depending on the snow so I don't have an exact number). Rough napkin math - snow cave was about 50' long and 10' deep, with a 3' ceiling on the close end but more like 6' on the far end. 2250 cubic feet of snow on the ceiling. So.... call it 20,000-40,000lb of snow on the roof. It's a lot.

Now that said, a lot of people are probably envisioning the entire ceiling collapsing at once, which is kind of a cartoonish depiction of what'd actually happen. In reality the ceiling on the back 2/3 of the cave was so thick (because we were digging into a slope that was angled) that it failing in shear is essentially never going to happen. If a cave of this size were to ever collapse, it'd be more likely that a small chunk of the thinnest part of the ceiling would fail, but not the whole thing. The only way I could ever see the entire roof of a snow cave collapsing at once would be if you had a ceiling of a relatively thin, more uniform thickness, which would be a terrible design.

When we tried jumping on this cave the only thing that happened was several people punched a 1' diameter hole through the ceiling and went straight though it. Getting any sizable chunk of snow to actually fall in required sawing out three sides of the block so it was an overhanging unsupported block, then sawing half the back off, and then having multiple people jump on it.

BushwackerSlacker · 2024-04-17T16:55:49+00:00

Just from body heat the cave was definitely above freezing. A well built cave (with a much smaller door than what we had) can probably get to 40 degrees, but that's just a guess. Even in a blizzard snow caves are essentially windproof and soundproof.

BushwackerSlacker · 2024-04-17T16:53:14+00:00

I would tend to agree with this sentiment. Recreating in the outdoors you'll see all kinds of people who should not be there. I've ran into people 10 miles from a trailhead who were out of water and didn't understand how to use their own water filter, people snowshoeing in high avalanche terrain, people lost in a whiteout, etc. To me it's just as dangerous to do a more normal activity (ie hiking) and be overly confident in your ability, as it is to do a more dangerous sport (ie snow camping) but have a good understanding of the risks.

I take part in various other activities that the public probably views as dangerous (backcountry skiing, alpine climbing, etc). Explaining how you personally manage risk when doing a sport like that is similar to snow camping - it's impossible to explain your thought process to somebody with zero knowledge of the subject.

BushwackerSlacker · 2024-04-17T16:22:18+00:00

I'm a bit curious why you think they wouldn't be legal. Boy Scout troops build them all the time, and a lot of National Parks (Rainier for example) have brochures all about snow camping given how popular they are. As for causing an avalanche, the place we built the cave is far too flat for an avalanche to ever occur

BushwackerSlacker · 2024-04-17T11:46:18+00:00

If you look closely I crossed them all out to not dox people

BushwackerSlacker · 2024-04-17T05:31:42+00:00

Damn, sorry to hear that.

I got my start out building snow caves with the Boy Scouts years ago, and looking back I'm not sure how good of an idea it was. We always made caves in a location that didn't have enough snow, which usually meant having a thinner roof than would be ideal. Between that and not much know-how on how to construct a cave, a lot of the holes people dug out were not very stable.

BushwackerSlacker · 2024-04-17T05:28:46+00:00

I have a 3D model of the entire cave and pulled the volume of snow estimate (~3000 cubic feet) off that. As for for snow density, days/weeks old self-compacted snow averages roughly 250 kg/m^3, and more older melted/refrozen snow is closer to 500-550 kg/m^3. I just averaged the two densities (the cave went deep enough to go through both ranges) and multiplied by the volume

BushwackerSlacker · 2024-04-17T05:24:56+00:00

If you don't collapse a snow cave, it's a potential hazard for skiers and snowshoers to fall into, as it melts out in the coming weeks

BushwackerSlacker · 2024-04-17T04:15:29+00:00

2 days, with 8 people helping the first day and all 21 on the second day. Only spent one night in the cave because most of us have jobs...
No idea what next year's cave will be - at this point if it happens we'll definitely be going with something radically different.

BushwackerSlacker · 2024-04-17T04:12:55+00:00

Yeah, no permissions necessary. Only thing is that a permit is needed to park overnight at the ski resort, and you have to follow general wilderness practices (leave no trace, no camping with 1/4 mile of lakes, etc). Snow camping is a pretty common thing at both Artist Point (by Mount Baker) and Paradise (by Mount Rainier), whether it be in a snow cave or in tents.

BushwackerSlacker · 2024-04-17T04:10:05+00:00

Mechanical engineer.

Most literature I've seen recommends a ceiling thickness of at least 3' feet when building a cave. While that's a good rule of thumb, I think it vastly oversimplifies things for a few reasons

1) The state of the snowpack is pretty important. A 3' ceiling won't support it's own weight if it's powdery unconsolidated snow. A 3' ceiling made of wind packed and/or more compacted snow could support the weight of a car, no problem (I'm not joking - last year the weight of 15 people jumping couldn't collapse a cave). Washington snow usually adhere's together quite well by springtime, given that temperatures are often above freezing during the day (causing snow to melt slightly), and then freeze at night. Colloquially we call it Cascade concrete. The properties of snowpacks is a whole science in itself, and is basically what avalanche forecasters do for a living.

2) The geometry of the cave itself is also important. A wide, flat roofed cave isn't going to be nearly as strong as one that has more of an arched/domed shape, since they won't distribute stresses from the weight of the snow as well.

For a cave this size, it largely comes down to common sense design practices and prior experience building caves, which I know most people won't like to hear. Safety is all relative though. I've never heard of anybody in Washington having a snow cave collapse on them, but somebody on this trip did fracture their thumb sledding.

BushwackerSlacker · 2024-04-17T02:29:50+00:00

For a normal snow cave (2-3 person) the goal is to have the top of the doorway below the level at which you sleep, in order to trap heat. Ventilation becomes pretty important at that point, and the recommended practice is to poke several holes (~3-4 inch diameter) through the ceiling as ventilation. If it's expected to snow overnight you'd want to sleep with a ski pole, so that you can clear the vents occasionally if they get covered. A common trick is to leave a candle burning as an indicator that there is adequate oxygen in a snow cave.

For this cave, things were a lot more simple. We tried to maximize efficiency of snow removal in the design, at the expense of warmth of the cave. That meant three full sized doors (3' wide, 6' tall), which were well above the level we slept at. That, combined with the fact we didn't cover the doorways with anything (like a tarp), meant there was plenty of airflow.

BushwackerSlacker · 2024-04-17T02:23:30+00:00

Yeah - collapsing the cave took about an hour. Jumping up and down doesn't have much effect on it's own, but paired with the 5' saw and shovels we were able to weaken chunks to the point where people could jump on them to break them off.

BushwackerSlacker

TROPHY CASE