Fuqian Yin emerges from the igloo he had been sealed in with a classmate during the Montshire Museum of Science's igloo build in Norwich, Vt., on Feb. 18, 2017. Yin a student at UVM is from China. Igloo builder Bert Yankielun behind him on the right had just cut the door into the igloo so Yin was able to emerge. (Valley News - Jennifer Hauck) Copyright Valley News. May not be reprinted or used online without permission. Send requests to permission@vnews.com.
Fuqian Yin emerges from the igloo he had been sealed in with a classmate during the Montshire Museum of Science's igloo build in Norwich, Vt., on Feb. 18, 2017. Yin a student at UVM is from China. Igloo builder Bert Yankielun behind him on the right had just cut the door into the igloo so Yin was able to emerge. (Valley News - Jennifer Hauck) Copyright Valley News. May not be reprinted or used online without permission. Send requests to permission@vnews.com. Credit: Valley News photographs — Jennifer Hauck

Norwich — Despite their exotic appearance, turns out igloos aren’t all that hard to build.

Using saws, pre-packed snow and plastic sleds — for transporting the heavy, frozen building blocks — visitors built about three dozen of the cozy structures in the space of several hours Saturday outside the Montshire Museum of Science.

“We’ll have a nice little village,” said museum employee Mike Fenzel, as construction got underway.

Bert Yankielun, who’s led the annual event for more than two decades, encouraged the crowd to team up into groups of a few families or half a dozen people.

Soon introductions were being made, blocks of snow cut, jokes cracked.

“I love to see this,” said Yankielun, a retired Cold Regions Research and Engineering Laboratory engineer. People, sometimes absolute strangers, “joining in an activity that has a tangible product at the end,” and maybe starting a new friendship.

He kicked off the event with a short talk for novice iglooists.

Due to its high air content, snow is a good insulator, and body heat alone can bring the temperature inside an igloo to 32 degrees or warmer, said Yankielun, who is the author of How to Build an Igloo, and Other Snow Shelters. When it’s minus 10 outside, “that’s a 42-degree difference.”

He also gave instructions, modeling building techniques as he spoke. Some participants hewed more closely to his example than others.

To make an igloo, blocks are set on an angle, leaning against one another for stability.

They’re also beveled toward the inside of the structure, creating the igloo’s signature shape.

Eventually, layer by layer, the shelter closes in on itself, leaving only a small opening on top, which is filled with the “king” block.

Finally, a small arched doorway is cut along the bottom, along with a fist-sized hole at about shoulder height, for ventilation.

As several people work on the igloo from the outside, someone else is stationed inside to help.

Just before noon, a group at the far edge of the “village” placed its final block and summoned Yankielun to cut the doorway. He did, and out crawled Ava Albrecht and her father, Chad Albrecht.

The White River Junction residents were greeted with cheers.

“You guys did a fantastic job,” said Heather Albrecht, Chad’s wife and Ava’s mother.

Not everyone went the beveling route, and some groups that wound up with large gaps simply laid slabs of snow across the openings.

“Everyone else is still working, and we’re drinking hot chocolate,” a man cheerfully observed.

One of the museum’s most popular events, this year’s build attracted hundreds of people.

Among them were 40 international students from University of Vermont, many of whom had recently encountered snow for the first time.

“Of all the days we could be doing this, it’s about as good as it gets,” said Emma Swift, assistant director of international student services at UVM.

Like any number of winter activities scheduled for the same time period, last year’s igloo build was canceled due to lack of snow, and many yesterday reveled in the warm weather and fresh snow. People whose children are on winter break this week said the activity was a good way to kick off their vacations.

“This is the start of the fun,” said Amy Deschaux, a Newbury, Vt., resident who’d brought her sons, ages 6 and 9, to the event for the first time.

After yesterday, the igloos will exist only in pictures and memories; due to safety concerns, shovel-wielding museum staff members knock them down following the build.

Nonetheless, there’s more outdoor fun to be had onsite; visitors can borrow snowshoes for trekking museum’s three miles of trails.

Aimee Caruso can be reached at acaruso@vnews.com or 603-727-3210.