uilding in the Arctic requires a stable foundation. However, cold-weather designers, architects, and builders face numerous challenges in this area, ranging from permafrost and frost heaves to a dearth of proper building materials.

“In a lot of communities, like the Yukon-Kuskokwim Delta and Bethel area, you can’t find gravel to save yourself, so you have to work with poorer quality materials like native silts and sands,” says Steven Halcomb, principal geotechnical engineer at Devise Engineering. “This causes all kinds of challenges, both in construction and in the long-term stability of infrastructure.”

The company, which specializes in structural and geotechnical engineering, has worked in the Yukon-Kuskokwim Delta, North Slope, Fairbanks, Canada, and Russia.

The remoteness of those communities makes adequate subsurface information hard to come by. “It’s often a challenge to do geotechnical and subsurface investigative work ahead of the design because it is cost prohibitive,” adds Jesse Gobeli, principal structural engineer at Devise Engineering. “While historical information can be used, it is not ideal.”

Many buildings in the Arctic are built on permafrost, which requires passively cooled steel piles (thermosiphons) to keep the ground from thawing. While used quite often, thermosiphons must be specially fabricated because they are pressurized vessels containing refrigerant.

An even bigger problem is differential permafrost, in which different areas within a region experience varying degrees of permafrost thaw, according to Robbie Lynn, general manager of UIC Construction.

“In southern regions of the North Slope, for example, there is an active layer that is increasingly growing in depth, causing structures to move,” he explains. “This means that when you’re installing piles for the foundation, you have to go deeper. On some projects, we’ve had to go 60 feet deep for pile to ensure that we’re locking into a stable frozen layer or a bedrock layer. And this increases the cost of construction substantially.”

UIC Construction has been building schools, hospitals, and other major facilities in the Arctic since 1978. While it has used many of the same construction methods over the years, it is also exploring Arctic engineering advancements. One such innovation is using thermo-charged piles. Instead of refrigerant, inert gas is used to actively cool the bottom of the pile.

“It’s not a new technology, but it is something that is being used more readily,” says Lynn, adding that UIC Construction has also been installing thermosiphons and thermistors (electronic thermometers) in order for clients to watch and monitor the ground temperature and ground movement of these buildings.

In addition to keeping heat from intruding into the soil, Arctic builders must avoid losing heat to the surrounding air. For example, designers and architects ensure that pieces of steel do not protrude from the exterior of the building envelope, pulling cold air back inside and creating condensation problems, among other issues.

“The envelope of the building has to be properly insulated, with moisture barriers in the right spots to avoid thermal transfer and moisture issues where at all possible,” says Nicholas Choromanski, principal structural engineer at Devise Engineering, adding that engineers who work in Alaska are required to go through an Arctic course to understand the special needs for construction in this environment.

It’s also important to protect builders working in dangerously cold temperatures, which often requires building a “bubble” to provide temporary heat.

“We’re building a school in Kaktovik, and in order to meet contract completion, we have to work year-round,” says Lynn. “Because we were installing the roof in December, we had to first build a tent that we could work under to start the exterior work.”

Lynn laughs as he recalls, “There was a huge rush to get the building dried in so we could work inside the building.” The tent kept the site at 40°F during the interior framing process, considerably warmer than the exterior ambient temperatures.

Lynn adds that freezable items require warm storage or must be flown in immediately before use. These materials include glues, paints, and even carpeting. “The rest of the materials we use can withstand low temperatures, but if floors and glues freeze, they’re trash and you’re out quite a bit of money, especially since you can only ship them up on one barge a year.”

While Arctic builders strive to follow international building codes, codes written in the Lower 48 are not applicable to some projects, including buildings elevated over permafrost.

“We have to kind of interpolate and come up with solutions that are not directly addressed in the code,” says Halcomb of numerous manuals that have been designed to help in the Arctic construction process. “And it can be a challenge to get everyone on board, from building officials to owners.”

While using the right materials is imperative, so is planning deliveries so that construction can continue uninterrupted, no matter the season. Not only are builders dealing with remote locations and challenging weather but the materials must arrive on-site on time.

“The barge schedule is a major factor when it comes to accessing sites; a lot of material is shipped up rivers that freeze in winter, so you have a very short window for hitting the barge cycle,” explains Choromanski. “You can airfreight materials in a C-130, but that’s an expense you want to avoid.”

The logistics schedule becomes the limiting factor in construction management. “You have to think through the construction schedule in order to get materials in place,” Choromanski says. “Builders like to install pile foundations in the spring when daylight returns and while the site is still frozen so they can move equipment there.”

Lynn agrees. “Working in the Arctic on the North Slope, logistics is—hands down—the most difficult hurdle,” he says. “Only one or two barges go up there a year, providing very limited resources to get materials to the North Slope. If you miss that barge, you push the project a year or have to fly in materials for a considerable sum.”

Unfortunately, costs are always going to be higher for construction in the Arctic and remote communities.

“Depending on if you’re on or off the road system, it can cost a tremendous amount more,” says Gobeli, noting that a building in town could cost $300 to $400 per square foot, but the cost increases to $1,500 per square foot for a more remote project.

Maintenance is also always an issue when it comes to any remote facility, with sea salt eating away at buildings in coastal communities, as well as wind and rust damage decreasing the life of a building.

“For this reason, we try to encourage clients to go with a more simplified system that is more easily maintained and doesn’t require specialized expertise,” says Lynn. “It is often difficult and cost-prohibitive to get experts to come to these smaller villages on a regular basis.”

Choromanski notes that it is imperative to hire companies with knowledge and experience of the Arctic that are familiar with the region and with sourcing and transporting the correct materials.

“If you’re working with someone in Texas designing a building in Utqiaġvik, you’re probably not going to have a successful project over the years,” he says.

UIC also relies heavily on interaction with Arctic communities and the support of local people to construct a successful project.

“That is hands-down most important thing about working there; without these communities, none of these projects would get built,” Lynn says, adding that UIC tries to use as much local hire as possible. “We try to hire everybody that applies from laborers to carpenters to equipment operators and cooks, and we also rent equipment, housing, and vehicles from local people to reduce the cost of construction. They are our most valuable asset.”

He notes that those familiar with working in the Arctic may also be better prepared for the unexpected challenges that those locations bring.

“The Kaktovik school project is the first job where I’ve had to hire polar bear guards; you have to look out the door before jumping into your truck to ensure that you don’t have an encounter with a bear,” he says with a laugh. “In Nome, the musk ox are just as dangerous as the polar bears. While these obstacles are unique to working in the Arctic, my nieces and nephew love it when I send them pictures.”

The Arctic is seeing the results of climate change firsthand, so architects, engineers, and builders with years of Arctic experience must rethink their methods as they face new challenges.

“There is a great deal of uncertainty moving forward related to climate change, and we’re having to create new strategies for how we deal with the problems we’ve always had making things work in the Arctic. It’s getting more difficult to achieve the same goals with methods used in the past,” explains Sarah Moyers, a civil engineer with UMIAQ Design, another subsidiary of Ukpeaġvik Iñupiat Corporation.

“While we could choose one method or another before, now we’re having to resort to combining different methods, throwing everything at the problem to get the same level of performance that we used to get with one solution,” she continues.

Moyers adds that, from a design standpoint, it is extremely challenging when what has worked well in the past is not a good indicator of how things will perform in the future.

“It’s a challenge on two fronts; not only do we have to reinvent the wheel a bit, but we also have to bring everyone with us and get them on board,” she says. “Telling clients that they need to do these things that will be more expensive is difficult, but they have to invest more money to get the desired result. It’s not that we’re being overly conservative, but conditions are changing.”

She gives the example of building a gravel pad on permafrost. “You’re essentially creating a buffer so that, as temperatures warm up, it doesn’t let warmth get into the frozen ground below so that it thaws and causes settlement. What’s written into the permitting document is that you need a minimum of four feet of gravel pad for long-term stability. But now that it’s getting warmer, the thaw is getting deeper, so you either have to add insulation or make the pad thicker. Both are expensive.”

Passive refrigeration (using thermosiphons to cool the ground without pumps or motors), is also becoming a challenge as temperatures are rising. This low-cost option is facing added costs as building owners install condensing units to actively cool the ground to keep foundations stable.

“Climate change is translating into needing bigger budgets for projects, which is difficult as budgets are already constrained,” says Moyers. “Planners often look at past projects to estimate what project costs would be with escalation factors, but now there’s more of a gap, and we have to account for these changes as well as ‘normal’ costs like inflation and the added costs of escalating prices on the supply side.”

Moyers approaches each case day by day, anticipating challenges that affect the design. “Will the site still be accessible? Will that site be underwater at some point? There’s so much uncertainty about what the future holds,” she says. “Designers, contractors, and facility owners will all need to work together to build resilient infrastructure in the Arctic that can adapt to the uncertain future associated with climate change.”