If you focus only on the reasons why European home builders are a decade or more ahead of the United States in the quality and performance of sustainable housing, you’ll miss the available, proven, and affordable technologies and tactics that can travel over the Atlantic to close that gap.
To be sure, a heavier (and accepted) dose of government regulation, more stringent (and mandated) energy-use and carbon-emission standards, and a deeply embedded cultural ethos that champion the collective good over individual aspirations all seem as foreign (and frightening) to American builders as wearing a kilt and eating the traditional Scottish dish haggis—and something they are even less likely to try.
But political and social differences aside, there’s a lot to be learned and applied from the European model of low-energy and low-carbon, yet comfortable and durable, residential design and construction. All it takes is a better understanding and some American initiative to bring it across the pond.
How Europeans define “off-site” or factory-built housing differs greatly from the “component framing” manufacturing that is employed in the United States.
Gerry McCaughey, who previously owned Kingspan Century, a SIPs-based, whole-house building system manufacturer in Ireland that produces 8,000 units a year, likens it to the difference between crafting a Mercedes and supplying steel to the factory. He bemoans the American model of local lumberyards providing open-frame roof trusses and wall panels that are assembled on site by stick-trained framing crews.
“It’s just a way for lumberyards to sell more sticks, not produce housing,” he says, and certainly not to a higher performance or environmental standard.
The European model, which accounts for about 30% of all new housing in England and perhaps 70% in Ireland, with similar market shares across the European Union, delivers precision that can’t be matched in the field. “In Europe, it’s an accepted fact that factory-controlled conditions result in higher quality,” he says. “And the higher the energy- and carbon-efficiency standards, the harder they are to achieve with on-site construction.”
In the United States, HUD-code and modular home shipments combined for 10% of the new-housing pie in 2010, a share that’s falling despite a greater emphasis on green building at a lower price point.
The key is accuracy through automation. Kingspan Century, for one, achieves framing tolerances equal to the width of a thumbnail, and its machines perfectly shoot six nails a second to secure a sheathing panel—a speed that enables the manufacturer to double the number of fasteners beyond the code-required pattern to deliver a stronger and airtight structure. “In the factory, the saw blade always comes down on the correct side of the line,” says McCaughey.
It doesn’t end there. European housing manufacturers are one-stop shops for entire home packages, at least to the drywall stage inside and the application of exterior finishes.
In addition to certified, four-man crews that can dry-in a two-story, 2,000-square-foot house in a day, companies deliver and stage drywall stacks across the slab and second-floor floor deck before the walls arrive, among other efficiencies that save time and reduce construction waste, the latter by perhaps 40%.
To match that performance, says McCaughey, American companies must accept and apply the whole package and philosophy of European automated home production. “The technology and machinery is available, but it’s just a tool,” he says. “You have to tell it what to do, and that means engineers instead of framers in the factory. It’s a fundamental difference.”