Can you dig it? Photo: Chewonki Semester School; Flickr

A quinzee is a giant pile of snow that you then hollow out to create a shelter—essentially it’s a build-it-yourself snow cave. Knowing how to construct one is a useful winter survival skill, a fun activity to do with kids, and a potential use for the mountains of post-blizzard snow that await much of the Northeast this week.

Quinzees are not difficult to construct–they just require the right snow conditions…and a lot of work. First, the snow. The simple test is this: If you try and make a snowball, does the snow stick together or does it crumble apart? If it’s the former, you’re in business. If it’s the latter, well…probably best to wait for next time. (More on this below.)

Next, start shoveling…and shoveling….and shoveling. The goal is to make a pile of snow that’s at least five feet high and ideally seven to eight feet high. This is a lot of work (several hours’ worth) just to build a snow shelter…but if you’re already digging out from a snow storm, you’re doing most of the work already. Keep in mind that the pile will radiate out a fair distance from its center as it gets taller—make sure and give yourself ample room in all directions to accommodate it.

Now your giant snow pile needs to set, or sinter. Snowflakes are delicate structures with lots of thin points radiating from a central node. If they are disturbed—shoveled into a giant snow pile, say—the points get broken off and the snowflakes compact together. The energy from this disturbance briefly melts the edges of the squashed flakes, which then freeze together to create a cohesive snow mass. The rate this occurs varies depending on the temperature and moisture content of the snow. Wet snow just below the freezing point bonds quickly; more granular snow in low temperatures takes longer, and may not sinter together at all. (Hence the snowball test, which provides a quick proxy for all this.)

In most conditions, the snow will sufficiently bond together in 60 to 90 minutes—go inside and get yourself some hot chocolate while you wait!

Snow set, it’s time to start shoveling into the pile. Start by digging a small entrance at the base—just slightly larger than what you need to crawl in—and then slowly work your way inwards and upwards. (Positioning the entrance on the downwind side will help prevent snow from blowing in.) If you’re working with others on this project, take turns digging out the pile while others clear away the snow being pushed out the entrance from inside. A smaller snow shovel or even large trowel is ideal for cutting away the interior walls in an initially cramped space.

As the cave gets larger, take care that you don’t excavate all the way through the interior wall and punch a hole in the pile. As a general rule, walls should be at least a foot thick—if you can see light filtering through the wall, it’s likely too thin.(Inserting sticks a foot deep from the outside of the pile helps you identify when you reach the proper thickness.)

Once you’ve got the interior dimensions set, smooth out the walls and set up shop!