Hi-Tech Heat Shields
Say “insulation,” and the first thing that comes to mind is thick, bulky, wool-like materials designed to be stuffed into exterior walls and under roofs to retard the transfer of heat or cold into and out of a building.
But there is another category that almost acts like insulation: radiant barriers. Wafer-thin materials with no inherent insulating properties, radiant barriers block heat transfer through roofs and, some companies say, walls. They include reflective metallic foils that are used alone or bonded to other materials, as well as liquid coatings that are painted or sprayed onto interior surfaces.
Not every shiny metallic material or coating reflects heat, however. Only products that are engineered or formulated to repel infrared radiation and meet specific industry standards qualify as radiant barriers under current regulations. Radiant barriers must have an emittance rating of less than 0.1 to meet ASTM C1313 and C1371 specifications. Liquid interior radiation control coatings must have an emittance rating of less than 0.25 to meet the ASTM C1321 standard.
Radiant barriers have been used in home construction for years, mainly in the hotter Sun Belt states where heat-blocking materials are needed and can be most effective. Early adopters used jerry-rigged foils and even metal sheeting to deflect at least some of the heat. But not all of those materials performed as intended; some products — such as tin and galvanized steel sheeting tacked to the underside of roof rafters — transferred ambient heat into the building.
Eventually, the practice of using reflective metallic foils as heat barriers caught on, and manufacturers began delivering products. Some performed as advertised, but because the science of heat reflectivity was not well understood until recent research, unsupported and sometimes wildly inflated claims of effectiveness often obscured the value of reputable products.
Industry research is divided as to the value of radiant barriers. Independent studies by the Florida Solar Energy Center and Oak Ridge National Laboratory show that radiant barriers in high heat-zone areas can reduce air conditioning costs by as much as $150 per year, but savings decline steeply in regions with lower ambient temperatures.
Other research has demonstrated that radiant barriers can improve heating and air conditioning in all climate zones, and a recent ASHRAE study conducted by ORNL showed that adding a radiant barrier generally improves the heat-blocking performance of standard insulation systems.
Michael Morris is a carpenter, author and journalist covering the home-building and remodeling industry.
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RBS radiant barrier sheathing is an oriented strand board with a perforated aluminum foil bonded to the interior face to prevent moisture buildup in the roof deck. (woodbywy.com)
ThermaWrap uses the optimum balance of Tyvek weather barrier and adds a low-emissivity metallized surface. (dupont.com)
LiquidFoil attic barrier is a vapor-permeable reflective paint for under-roof surfaces. It blocks up to 84% of heat radiating into or out of a structure. (henry.com)
Solarbord OSB radiant barrier sheathing has a 3% emittance rating and 97% reflectivity, which can reduce a home’s air-conditioning requirements by up to ½-ton. (norbord.com)
A Carolina plant takes pride in its OSB
ELKIN, N.C. — The Weyerhaeuser mill in Elkin, N.C., is a classic Made-in-the-USA manufacturing story.
Raw material in the form of “stumpage” — the mill executive’s term for “logs”— lines up at one end of the 186 million-sq.-ft. facility. Rolling out at the other end are neatly stacked and wrapped pallets of Weyerhaeuser Edge OSB, as well as Weyerhaeuser Edge Gold (photo 1).
(The regular Edge product guarantees: “No delamination.” The Edge Gold guarantees: “No sanding. No delamination.”)
The Elkin facility is one of several OSB manufacturing locations Weyerhaeuser operates across the country. Others are in Louisiana, Michigan and West Virginia. The Elkin plant’s highly automated, 24-hours-a-day, 7-days-a-week manufacturing process employs more than 133 people.
One of those employees is Chris Phillips, the plant’s technical team leader who recently led a group of visitors on a walk-through tour. Speaking through a radio system to overcome the noise of the machinery, Phillips showed off the plant’s ability to shred the logs, treat them with adhesive, orient the strands — one of many technical marvels in Elkin — and stamp them into shape (photo 4).
“This is not flakeboard,” Phillips said, bristling at the derogatory term. “It is an engineered product, engineered to give the customer a product that will work.”
He ticked off the attributes that the plant carefully measures and controls: thickness, moisture content and orientation of the strands — all governed by another insider term, “PCL” or “process control logic” (photo 3).
To a first-time visitor, the row of logs awaiting their turn for the assembly line seemed impressively massive (photo 2). However, Phillips explained that the row of stumpage was relatively low, the result of rainy weather in previous days, which prevented trucks from harvest.
The plant opened in 1986 and has since grown to about twice its original size. Running at full capacity, the mill handles about 1,800 tons of stumpage per day. Still, it’s considered a small to medium-sized facility, by Weyerhaeuser standards.
Amid all the stumpage, a clear sustainability story also plays out at the mill. The facility is certified by the Sustainable Forestry Initiative. It also gives back seedlings to private land owners who supply full-grown trees. Since 1997, Weyerhaeuser has given away some 5 million seedlings.
The plant also creates a lot of bark. Bark isn’t a strong enough ingredient for its OSB product. As a result, the bark is sold off to landscape companies as mulch.
A little package with big messages
Without some key elements of the packaging, the Little Big Shot has — in the words of its chief marketer and ambassador David Kurrasch — no shot at winning over the consumer during that all-important, first-impression in the aisle.
About the size of a golf ball, the brass nozzle with a ball-bearing control mechanism benefits from a blister pack that simulates the nozzle in action. The packaging shows one end of the nozzle attached to a hose, while the other end shoots a powerful spray of water.
The package also tells the story of performance, conservation and — perhaps most significantly — a Made-in-the-USA story with the added emotional power of “assembled by disabled U.S. veterans.”
“We didn’t set out by saying, ‘Let’s have a veteran built product to use as a marketing strategy,’” Kurrasch told HCN. “We feel very fortunate to have found the veteran groups to work with us. And we wanted to help put people to work.”
Kurrasch, the entrepreneur and founder of K-CO Innovations, said the first objective was to find the right suppliers to turn the brass in the United States. Research lead to two: Alger Manufacturing in Ontario, Calif., and Avanti Engineering of Glendale Heights, Ill.
Two factories were necessary to meet the in-season volume of 50,000 nozzles per week, he said. Assembly takes place in sheltered workshops of veterans hospitals in Long Beach, Calif., and, more recently, Milwaukee.
An immediate marketing challenge for the product was to make clear to the customer that it was a nozzle, and not a coupler or some other form of hardware.
“Typically, hose nozzles have handles,” Kurrasch said. “They have dials, they’re much bigger than this. They look different. The package had to tell people from 4 ft. away that it is a hose nozzle.”
The success the nozzle has had at Bed Bath & Beyond indicates the packaging’s success as an impulse purchase. “People don’t tend go into Bed Bath & Beyond looking to buy a hose nozzle,” he said.
Kurrasch says the veterans, many of whom are disabled beyond the ability to find work elsewhere, are precise and engaged in the assembly of the product. And the message on the package — though not aggressive — resonates with consumers.
“I’ve heard stories from people who didn’t have a need for a new nozzle, but they wanted to support a product that was providing jobs for veterans,” Kurrasch said.