Are Quonsets the rural residences of the future?

What’s semi-cylindrical, made of steel, and is changing the way we think about building homes and cottages? Quonset huts. While their futuristic appearance may seem ultra-modern, they’ve actually been around since the 1940s. The structures were developed during the war to quickly and easily house military folks. Bases in remote locations would receive the huts in pieces, with personnel taking as little as a day to fully assemble one, from the corrugated metal shell, steel frame, and wood fibre insulation, all the way down to the plywood floor.

Quonsets have come a long way since then. Farmers have used them for decades to store livestock, equipment, and hay bales, and now, people are living in them. When compared to traditional “stick built” structures, Quonset homes are better able to withstand the elements, and they release zero carbon emissions (when they run on renewable energy sources, such as solar power).

Plus, “Quonset homes can cost up to fifty per cent less than a similar high-performance conventional build,” says Andy Thomson, the founder and principal architect at the Algonquin Highlands, Ont.-based firm Thomson Architecture. He’s built two Quonset homes (including his own) and has designed more than 50 for clients in Canada and across Europe.

Thomson estimates you could build your own cozy, energy-efficient Quonset abode for around $320,000, including materials, labour, overhead costs, and permits, plus the professional services of an engineering and architect team—which you definitely need. “You can’t just DIY one of these things, otherwise you’re going to end up with a high school shop project.” Thomson explains the Quonset kits you can get online, for example, are intended more for storage than human occupancy. “The steel isn’t engineered to meet higher load and resilience requirements for human habitation, nor is it able to support finishes and insulation. That’s why you need a team of professionals.”

Cottage building materials that are better for the environment

But why would you want to build a Quonset home or cottage in the first place? Durability, for one thing—and longevity. “A properly built Quonset home could easily last you 100 years,” says Thomson. And because of their sturdy metal shell, made of two “skins” or layers of steel with spray foam insulation in the middle, you’d never have to worry about common annoyances that plague traditional wood-framed homes or cottages, such as leaks from heavy rain or damage from high wind and hail.

“The outer steel layer has sealed edges, the spray foam insulation is weather impervious, meaning it won’t allow any fluid through, and the interior layer is also waterproof,” says Thomson. Leaks be gone!

When it comes to those high winds, Thomson says Quonsets have more than double the wind resistance of a regular home. “The steel shell is bolted onto threaded rods embedded into the concrete foundation. They’re locked together and work as one system.” That means you don’t have to fret about losing your roof during a severe weather event, such as a tornado or hurricane. “The steel might warp, but it’s not lifting up, and it’s certainly not blowing off.”

Quonset homes are also fire resistant. That’s (again) thanks to their metal construction. When a residence is destroyed by a wildfire, up to 90 per cent of the time it’s from a flying ember. But steel is non-combustible and therefore doesn’t burn. “When a flying ember lands on a Quonset, nothing happens,” says Thomson.

How to build a cottage that will last a lifetime

Aside from their seemingly indestructible exterior, Quonset structures are incredibly airtight, meaning no drafty winter mornings, minimal heat loss, and next to no energy waste. “Air can’t move through the steel when it’s bolted together and caulked, plus we enhance it with air-sealing and membrane-detailing measures, like applying caulking strips between the steel panels and using special construction-grade adhesives on the end walls.” Thomson says when they measured the amount of air leakage at one of their builds, it clocked an air change rate (the number of times air in a space is replaced per hour) of 0.46—and that was before the enhanced measures. For comparison, an R-2000 certified home—considered one of the most energy-efficient home types in North America—has an air change rate of 1.5.

This means mega energy savings. The average Canadian home uses about 85 gigajoules (a unit of measurement for energy consumption) of energy, including electricity and natural gas. Thomson says Quonset homes use about 50 per cent of that. When he was living in his own in Quebec—where he was more energy conscious—he used about a quarter of the national average.

But isn’t a highly airtight building an ideal breeding ground for mold? “It’s something you need to address with proper ventilation, either by installing a heat recovery ventilator or energy recovery ventilator,” says architect Earl Parson, who is the founder of Clever Moderns, an Arizona-based firm that specializes in Quonset designs. The former, an HRV, is often better at mitigating humid conditions because it uses the heat from the humid indoor air to warm the fresh incoming air without tracking more humidity from outside. ERVs work similarly, but they also allow for added humidity to flow into the home, making them a good choice for climates that are drier.

Parson has his own “Quompound,” a 10-acre property in northern Arizona near the southern rim of the Grand Canyon (which, yes, does get snow!) with four different Quonsets ranging from 300 to 1,000 sq. ft. in size. “Even in our 600-sq.-ft. Quonset HQ, we’ve realized how much we need to manage our moisture, especially in the winter. It can build up from everyday activities like cooking, washing your hands, and just breathing and perspiring.”

Adding passive ventilation to your cottage

And since the structures have such open layouts, with lofty ceilings and often minimal interior walls, aren’t they noisy? “When you put up the metal shell, the Quonset has a tinny echo. But the minute you put end walls on, the sound is captured differently and that echo goes away,” says Parson.

For all of their benefits, then, is there a future where Quonset cottages will be popping up all over Canada? Maybe. “People are thinking differently about how to build a cottage or home. They’re asking what the optimal building of the future looks like, and if it looks like a Quonset, then so be it,” says Thomson. “Plus, curves are cool.”