Turn A Snow Fort Into A Snow Fortress With These Tips From A Polar Engineer

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If the heavens just dumped a foot or more of fresh powder on your front lawn you have two options: A) Go back to bed; pray for an early spring. B) Build something that makes your neighbor’s snowman look like the hack job it is. Dr. Bert Yankielun is a Doctor of Engineering from Dartmouth who wrote the book on building snow shelters — literally. It’s called How To Build An Igloo And Other Snow Shelters. If you follow these instructions, your little frozen fort can withstand a horde of White Walkers — and their creepy kids.

There Are Two Types Of Shelters

Quinzee: Just a simple mound, hollowed out. “It’s like a VW Bug made of snow,” says Yankielun.

Igloo: “A cartoon igloo is a hemisphere. A real igloo will have a parabolic cross section. More beehive than half a basketball.” But you totally knew that already.

One Thing You Should Know About Snow

“If you can make a snowball, you can make a snow shelter,” says Yankielun. So while the wet snow that is constantly freezing and thawing throughout the day isn’t great for constructing an igloo, it’ll be fine for a quinzee. You’ll need to do a bit of prep to make some structurally sound igloo bricks.

Gather These Tools

• A snow shovel. Like the one you curse at when shoveling the driveway.
• A rusty saw. “Don’t use the one for woodworking. Once you expose it to ice it isn’t good for anything but building igloos,” says Yankielun.
• An entrenching tool (or if you’re not a mountaineer or WWI vet, a trowel).
• A ski pole.
• Children.

The Easy Way: Make A Quinzee

• Grab a snow shovel to make a pile.
• Hand that shovel to your kid.
• Stick twigs a little less than a foot into the snow like a porcupine. “I got this tip from the Girl Scouts. You’re digging blind, but if you put the twigs at strategic locations, the ends will tell you that you’ve gone far enough.”
• Hollow it out by hand or use the entrenching tool.
• Don’t forget to punch a fist size hole in the roof — because all of your huffing and puffing will quickly increase the level of carbon dioxide inside and decrease the level of you being alive.

The Advanced Way: Make An Igloo

• Prep your building material overnight. Make a 10-foot by 10-foot “sheet cake” that’s also about 2-feet thick.
• Pack it down with a shovel or snowshoes.
• Now you have your own quarry. Cut blocks out of the snow about 2-feet long, 1 ½-feet high, and 9-inches thick. Or the size of a cinderblock.
• Point at your smallest child and tell them to make a Snow Angel. This will be the diameter of your igloo. Stomp around the perimeter to make sure it’s flat.

• First create the initial ring of blocks.
• Find the center (you can just stick a ski pole or something in there).
• Use the saw to cut vertical spirals at an upward angle so that the next set of bricks look like they’re going up a ramp. If you don’t, you’ll wind up standing inside a snow tube.

• Build up, making sure that each brick is lying across the seam of the one below it. (See: LEGO Master Builder.)
• The last brick that you stick in will be your “king block.” Have an adult (you or another parent) go inside to make sure it fits like a cork.
• It’s time to put in a door. Look for a good lintel. It should be a big block that spans two blocks. Use your saw to chunk out an arch in those lower blocks. Entre!
• Once again, make an air hole about 60-degrees off-center. Because, breathing.

How To Turn a Shelter Into a Fort

Maybe you’d like your peacetime igloo to be an all-out snowball rampart? Yankielun says that the principles stay the same. Use the first igloo steps, but stop building half way up. The open top will be perfect for lobbing a few snow grenades or mounting your snow M2 heavy machine gun.