Remember the cool Sears Kit Homes from the early 20th century? Whether it’s for your primary home or that weekend getaway cabin you’ve always wanted, buying a kit home in which the components are manufactured in a controlled environment and shipped to your home site could be a greener, more environmentally friendly option. And no, we don’t mean a mobile home.
Panelized Building Systems Some of today’s most interesting energy-efficient kit homes are built using panelized building systems. According to the National Association of Home Builders, a panelized building system uses advanced technology, quality materials and a controlled work environment to build floor, wall and roof systems to construct an energy-efficient home in less time.
However, the panelized building system category includes a range of products, so it’s important to define what a green, energy-efficient home means to you and to do your research before you buy. For example, according to Michael Morley, the operations manager at SIPsmart Building Systems in Lawrence, Kansas, many panelized building systems are the same as site stick-built systems (except that they are pre-made in a factory and shipped to a job site), and this does not make them green or energy efficient. Structural Insulated Panels One type of panelized system is structural insulated panels, aka SIPs, which are prefabricated panels made of insulating foam sandwiched between two structural facings, usually oriented strand board (OSB).
(image courtesy Artecon)
Morley’s top five reasons to build a SIP home: 1. Increased energy efficiency. A SIP home is an airtight envelope and can utilize a smaller HVAC system, saving energy and money. 2. Improved indoor air quality. Reduced air infiltration increases control over the indoor environment, which means having a healthier home. 3. Durability. The SIP system is proven to be stronger than stick-built systems, providing durability and resistance to winds and seismic forces. 4. Labor savings. Precut SIP panels are erected quickly, which saves labor. 5. Waste reduction. Building a SIP home creates much less site waste than a conventional home, which is good for the environment and your wallet. Sarah Susanka’s Not So Big Bungalow Morley has worked with renowned architect Sarah Susanka and Extreme Panel to create the Not So Big Bungalow, Plan 454-13 (shown at the top of this post), a beautiful 1,600-sq.-ft., Craftsman bungalow available as a SIPs kit, that’s inspired by the architect’s interest in the 20th-century Sears Kit Homes. The home features wood SIPs components, has an Energy Star Plus rating and a good provisional HERS rating, and can be delivered prewired for alternative energy systems.
Once the kit arrives at the site, Morley estimates that it takes two weeks or less to close in the building shell so that it’s ready for the interior work. The bungalow is engineered for most areas of the lower 48 states, and engineering is also available for higher elevations or special seismic or wind velocity zones. When it comes to the budget, Morley says that, to complete a Sarah Susanka house, homeowners should typically have a budget of between $250 and $300/sq. ft. Real People Homes If you like the idea of a kit house, but you have a more modest budget for your home or getaway cabin, Real People Homes (RPH) based in Leakey, Texas, created a line of basic kit homes by asking the question what can be eliminated from a conventional home. The answer turned out to be trusses, drop ceilings, attics, wood, plasterboard, plywood, floor covering, and duct work.
RPH homes are Energy Star homes built using light-gage steel and EPS foam panels [expanded polystyrene (EPS) is "a rigid and tough, closed-cell foam" according to Wikipedia] in a light coating of cement, according to Tim Donovan, who represents RPH in New Mexico.
Attic insulation is augmented with a double-sided radiant heat barrier made of the material that keeps rockets from burning up during reentry, the flooring is polished and sealed cement, and, since the homes don’t include organic materials, they resist mold, mildew, water damage and insect infestations. These homes have a good HERS rating and perform well in the Southwest, West Coast, Northeast, Southeast and the Tropics, Donovan says.
Redefining Affordable According to Jim Druffel, an industrial and building designer who also represents RPH in New Mexico, what makes these homes affordable is the fact that, when the walls are constructed at the factory, the studs are interleafed with the foam, electrical is placed in conduit in the walls, and the walls are closed and delivered to the job site ready to be textured and painted. Onsite drywalling and insulating are unnecessary, and onsite electrical and plumbing work are kept to a minimum further reducing costs.
Since the walls arrive at the jobsite closed, RPH works with a third-party inspection agency to approve the panels at the factory during construction. Once the panels are delivered, a home can be built in approximately three days, Druffel says. The panels are lightweight and can be erected without using a crane by a small work crew using stepladders and battery-powered screwdrivers. To build a Real People Home, homeowners should plan on a budget of between $80 and $90/ sq. ft., not including infrastructure, Donovan adds.