Project Update: A Sustainable Family Lake House

OPTI_Brtltt-(5) This energy-efficient lakeside home is designed for an extended family who has been vacationing in New England for generations. The home combines the rustic charm of a New Hampshire cottage with cutting-edge building technology and sustainability.

At around 3,100 sf, the design requirements were to blend in with the existing Lake House vernacular of the neighborhood and the heavily wooded lot, frame views of the surroundings from inside the house, and fit into the lakeside cottage community in scale, proportion and style. Nestled into trees (carefully preserved during construction), the wood shingle home has a roomy screened-in porch and built-in BBQ—a lake retreat must. The colors and textures of materials reflect the laid-back community and surroundings.

lake house elevations The home’s vaulted timber frame and prominent stone fireplace lend a rustic lodge feel, yet remains intimate and cozy. The building has an advanced thermal envelope using prefabricated structural panels, sealed with gasket and tape technology for superior airtightness, moisture control and indoor air quality.

OPTI_BRTLTA2A folding glass wall opens the main living areas to the screened in porch, with lake views and an outdoor gas fireplace and cooking/dining area. One of the three, second-floor bedrooms is a spacious bunkroom accommodating eight or more—all are open to the living/dining area below via a shuttered gallery, retaining the theme of an open gathering space. The kitchen, dining, alcove seating area and great room all have views of the gas-burning, fieldstone fireplace.

Sustainable Building Features:
-Programmable bath fans.
-Multi-zone radiant heating.
-High-efficiency Low E windows.
-Eco-friendly dense-pack cellulose insulation providing R-Values of 35 in the walls and R-44 in the roof.
-No mechanical air conditioning—ceiling fans, window placement and stack effect design provide natural cooling.
-A timber frame constructed of sustainably harvested timbers salvaged from fire or insect-damaged forests.

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Unity Homes Celebrates 2nd Anniversary

“The typical American home is a performance dinosaur, and is too much of a long-term burden for homeowners and society. Unity Homes aims to help make this species extinct.”     

Tedd Benson

Governor-2013-16

New Hampshire Governor Maggie Hassan (standing, center) visiting the Unity Homes production facility in October 2013.

On October 9, 2012, Bensonwood launched Unity Homes with the goal of making ultra-efficient, off-site-built homes affordable for the average home buyer. To date, Unity Homes have been built along the East Coast as far south as Asheville, NC and as far north as Montpelier, VT, and have been praised as possibly the “greenest prefabs on the market” by TreeHugger’s Lloyd Alter.

Designed to consume 50 to 75 percent less energy than standard newly-built homes, Unity Homes currently has four distinct 2 to 4 bedroom styles ranging in size from 1,028 to 2,450 sq ft. The home models are the Tradd (a classic tall cape), Xyla (an American bungalow), Värm (a Swedish contemporary) and Zūm (a passive solar optimized modern). All four of the highly-customizable styles have been built.

3 VARM SAMPLES

Three interpretations of the Värm design shown here illustrate the highly-customizable nature of Unity Homes.

In the two years since its launch, Unity Homes has developed ways to raise the quality and performance of sustainably built homes while continuously trimming cost to make them ever more affordable. The company has already reached its original goal of trimming the typical build time to 30-35 working days for most projects and expects to get it down to around 20 working days in the future.

History

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Although Unity Homes first appeared in 2012, the seeds of the idea began much earlier. In 1991, Bensonwood began the long-term process of standardizing home production using computer-assisted design (CAD) software to optimize floor plans.

“I have long believed that the average American home should have a much higher standard of build quality, durability and energy performance,” Tedd Benson said in a 2012 Green Building Advisor article about the Unity Homes launch. After years of building a reputation for higher-end timber frame projects, Benson and the Bensonwood team wanted to bring his building innovations to the market-rate factory-built world.

There was also a philosophical element to Benson’s plan, describing the typical American home as a performance dinosaur, and too much of a long-term burden for homeowners and society. Then, as now, he wants to make that species extinct and transform the industry by offering an affordable home at a higher standard of efficiency.

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The LEED Platinum-certified, Net-Zero Energy president’s home at Unity College in Maine.

In 2008, Bensonwood received critical acclaim for its roles in fabricating the LEED Platinum-certified Unity House, a net-zero energy residence built on the campus of Unity College in Maine for the college president and his family.

The project was important, not only because the building was designed to maximize energy performance, but because it highlighted the Passive House standard for airtightness—the most cost-effective and easily achievable aspect of the Passive House standard.

Inspired by the project’s success and what the company learned from it, four years later Bensonwood launched a separate company producing high-performance prefab houses. The company was dubbed Unity Homes because it was thought the perfect name to express the democratic, egalitarian nature of these homes designed for the average American family.

Despite being in the throes of the worst housing crisis since the Great Depression, Benson realized that the company’s Bensonwood’s Open-Built® “operating system” capabilities and production capacity were being underutilized and warranted expansion. Tedd Benson also wanted to avoid reducing staff and a new division would allow the company to weather the housing downturn.

A 40-Year-Old Startup

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Building system team members assembling wall sections for an early Unity Home.

Unity Homes’ strategic vision began with a seemingly simple premise. “What if building only took 30 working days, all costs were known, the house quality was above anything the buyer had previously experienced, and the home could be net-zero-energy forever?”

For nearly a year, the entire Bensonwood team worked together to design and engineer the Unity Homes offerings and develop all the information, renderings and floor plans.

early unity college planning session

An early Net-Zero Unity House planning session.

With no outside funding and many long hours, the company created a “40 year old start up,” Tedd Benson quipped at the time. In the end, Unity Homes was able to achieve both energy performance and price point goals with its high-precision panelized construction methods, keeping 60% of construction inside its production facility. Each home is organized into easily accessible “layers,” making for easier future upgrades and repairs.

By the time Benson announced the new company’s launch in an October 9 post on his blog site,The New House Rules,” Unity’s first two homes were already in production.

Montage: A Streamlined Process

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In Montage Building, pre-designed, high-performance elements can be easily reordered to fit homeowner budget, lifestyle or location.

The Unity Homes team sees these houses as more than another entry into the green prefab market, but rather as a complete rethinking of how houses are built. Many people in North America buy houses that might not last as long as they do; Unity houses, like the custom Bensonwood homes, are designed to last for generations.

Additionally, instead of prefab or modular, Tedd Benson prefers the term “montage” to describe the homes, which essentially means “assemble” or bring together disparate elements to form an integrated whole. That use of montage refers not only to the building process where panels are assembled at the home site, but also to a unique approach to vernacular design. The homeowner would not incur the cost of hiring an architect, nor would they be choosing from a limited product line as with most modular or prefab houses, but be allowed a range of customization to fit their lifestyle, budget and location.

Produced in Bensonwood’s Walpole, NH “studio,” the panelized wall, floor and roof assemblies are typically ready to ship to site in a few weeks. This work is concurrent with site prep and in parallel with other component fabrication such as the precision-cut beams and millwork.

The onsite assembly of the weathertight shell is usually accomplished in one to three days, depending on complexity and garage options. From there, Unity Homes can be finished quickly because of the open layout and packaging of systems, such as pre-assembled HVAC modules. While a standard new home takes 150 days to build, Unity Homes can now shave the building cycle down to as little as 30-35 days.

The Unity Homeowner Experience: “Rewarding and Fun”

Tedd Benson has always stressed the importance of owner involvement in the homebuilding process, but J.C. and Nancy Woodward of Fitzwilliam, NH, took it to another level. J.C. and Nancy initially came to Bensonwood looking for a custom home, but after several discussions with associates, architect Chris Adams suggested they consider one of the new Unity Homes about to be launched. The Woodwards were intrigued and chose the Värm style—J.C. also chose to act as general contractor to cut cost.

Varm Unity Home

An early Värm in New Hampshire was finished by the owners to reduce cost.

The site was prepped in late 2012, production began in February 2013, and by April the crew arrived with the home’s shell, which Woodward would finish out himself with help from some local subcontractors. Having built another house 25 years prior, he expected the typical chaotic construction scene with a host of endless problems to address. Because of the obvious attention to detail and quality, Woodward says, any problems that arose were small ones and easily solved.

J.C. was there from 7 a.m. until evening every day and was stunned at how quickly and smoothly the home came together. He was also impressed by how, “every person on the Unity team deeply cared about my project’s success.” From architect Chris Adams “wringing function from every square inch” to make the house feel a lot bigger than its 1,700 SF footprint, to project manager Tony Poanessa repeatedly “going the extra mile” to make the project run smoothly, Woodward describes the experience as rewarding and fun. In fact, he was so inspired he is now taking a CAD drafting course at Keene State College and hopes to work as a project manager himself someday.

High-Performance

The airtight homes possess many of the standards of passive house: optional triple-pane windows, high levels of dense-pack cellulose insulation (R35  OBPlus Walls® and R44 roof), buttoned-up building shells with a Passive House level of airtightness to 0.6 ACH @ 50 Pascals or better, energy recovery ventilators, air-source heat pumps and more to reduce energy use by 50% to 75% compared to standard new houses. The homes’ operational efficiencies with low energy loads mean less power use and smaller HVAC systems. They’re also capable of achieving net-zero energy if the owner decides to add a modest solar electric system.

Health & Comfort

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Stressing health and comfort as much as energy efficiency, Unity Homes are well-lit, quiet, draft free and moisture controlled.

In addition to the energy-saving features, standard specifications of the two- to four-bedroom homes include low-VOC paints and finishes, all-electric water heaters, Moen fixtures, EPA WaterSense toilets from Kohler, and high-quality woodworking and cabinetry.

In addition, they’re comfortable, light-filled and spacious, have great air quality and are fitted with high-quality materials, finishes and fixtures. Another less-considered element is that they are quiet—something too often missing in our homes. Silence is a feature increasingly accepted as vital to health and emotional well-being; and with doors and windows closed there are no traffic sounds from the street, airplanes overhead, barking dogs or noisy neighbors. Tedd Benson often refers to these as providing vital “sanctuaries or “sacred spaces” for family.

Adaptability

Heavily influenced by the thinking of John Habraken and Stewart Brand, Benson and associates developed the Open-Built platform to allow simple modification of structures as occupant needs change. The central idea behind Open-Built is to “disentangle” the building’s interior and exterior systems into separate, functional layers, which improves the efficiency of the construction process. That disentanglement also allows for long-term access, meaning homeowners and professionals can accomplish changes, upgrades and renovations with less demolition and rework.

All systems within the Unity Homes will be continually scalable, with most mechanical and space upgrades able to be accomplished by the homeowners.

Cost

3D FLOOR PLAN MODELING

The ultimate goal of all green prefab manufacturers is to get the quality control and efficiencies possible in a factory at an affordable price. A common complaint is that Unity Homes and its peers are not affordable when compared to conventional stick-built housing, despite the fact that these are not conventional houses.

In truth, cost for this “beyond code” design and performance is competitive with current on-site, building-code-based construction when all factors are considered. These include: resale value, energy bills, maintenance and repairs, health effects and remodeling cost.

Nevertheless, driving down cost is a top priority in the Unity Homes mission. Unity plans to broaden the market for their homes by continually reducing cost to match the cost of conventional building, which varies widely between geographical regions. The company has already achieved this in many areas of the Northeast.

Eventually, Benson says, as more builders use and demand high-performance products, competition will increase among manufacturers, creating a virtuous cycle of improved performance and lower costs. He is emphatic, “Americans deserve better homes, and the industry has the capacity to build them, we’re just not doing it on a consistent basis. If this type of building was industry wide, the costs would drop for everyone.”

Future

OPTI_MEIR-AUER-5June-2013-001Tedd Benson is pretty clear about his future plans for Unity Homes: expanded production facilities across the country to lower shipping costs, continual improvement in the production process, and lower cost.

Eventually, Unity Homes wants to merge its current panelization process with modules that would allow Unity to complete mechanical rooms, bathrooms and kitchens at its facility, and leave only 20% of the building process for on-site construction.

Last, but not least, he wants Unity Homes to stand as a sustainable model for the industry, and with that to change how Americans view homebuilding from something to be dreaded and endured to something that is rewarding and even fun. In the end that will be a source of healing not only for future homeowners but for the planet.

Texas Prefab Lake House

austin texas lake house 1 An admitted This Old House fanatic, Matt Risinger had grown up watching the PBS television series when, in 1989, a program aired that would change his life. The Wickwire Barn Series—the second time Bensonwood had appeared on the long running home improvement program— featured Tedd Benson and an old barn being converted to a new house: a project Matt had dreamed of building for himself someday. It became the seminal moment in his decision to become the best builder he could be.

Mette Aamodt AIA and Andrew Plumb AIA

Mette Aamodt, AIA & Andrew Plumb, AIA

Fast forward nearly two-and-a-half decades, and architect Andrew Plumb of award-winning Aamodt / Plumb Architects in Cambridge, Massachusetts, is looking for a builder to help assemble and finish out a highly custom modern timberframe ranch home he designed for a special client he has known for years. The lakeside projectTEXAS PREFAB, expected to approach near Passive House standards, would have an aggressive build schedule of one year, and it needed to come in at a fixed budget—so Andrew knew it had to be done right. His first thought was to call Bensonwood for its expertise in the sustainable fabrication of high performance homes, and his second thought was to call green builder, Matt Risinger, now of Risinger Homes, to say Tedd Benson’s company would be fabricating and installing the home’s shell. With the name “Benson” still fresh in his mind after a quarter century, Matt jumped at the opportunity. The home plan, viewable on the Aamodt / Plumb website, is a interpretation of the Texas Ranch vernacular, with two gabled buildings joined by a light-filled entry hall. Designed for a young family, this prefab home strives to create a relaxed, contemporary feel through the use of natural and reclaimed materials, ample daylighting and a thoughtful relationship to the site.

MATT RISINGER

Austin, Texas green builder Matt Risinger

“We sought to create a warm modern atmosphere through the interplay of simple forms, materials and natural light,” says Plumb. The play of the modern and rustic is achieved through material choices and elemental forms. Japanese (Shou Sugi Ban style) charred wood siding, mesquite and ash flooring, and an oversized FireRock masonry chimney and fireplace add a dramatic touch both inside and out. texas green prefab architects renderingThe light-filled open interior, with its elegant but simple timberframe, richly-finished flooring and high-end fixtures, perfectly complements the striking exterior while framing the surrounding views. Matt Risinger asserts that, “The most sustainable house is a pretty one. Architect-designed houses will be loved and cared for because they are beautiful. Ugly houses will fall into disrepair and be torn down eventually.” fireplaceBeyond the aesthetics, this house was designed to coast through the hot parts of the day with little need for air conditioning. This is achieved through rigorous attention to air sealing and our panelization process using super-insulated walls. All the exterior claddings are installed over a rain-screen air gap. The roof, wood siding and even stucco have an air gap behind them so that the potential for water intrusion over the life of the building is minimized. Risinger installed super-efficient mechanical equipment to make the best possible use of the resources consumed. 95%+ efficiency gas equipment, super high-efficiency AC, Ultra-Aire Split Dehumidifier prevents mold and allows the owners to keep thermostat settings high when the building is unoccupied.YOUTUBE TIMELAPSE IMAGE You can watch Matt Risinger’s YouTube video of the home being assembled here. Once the project is completed and finish photos become available, we will revisit this home to detail its space plan. Stay tuned.

Passive House: The House of the Future | Sheri Koones

Passive House: The House of the Future | Sheri Koones

smaller_version_400x400Posted: 05/08/2014

From our old friend Sheri Koones in the Huffington Post yesterday. We appeared in prefabulousher popular 2012 book Prefabulous + Almost Off the Grid: Your Path to Building an Energy-Independent Home.

The Passive House (or Passivhaus) (PH) was first established in Germany and is quickly becoming a standard in many parts of the world, including the United States. Whereas other important standards, such as LEED), focus on many environmentally friendly aspects of the home, such as site location, sustainability, materials, water efficiency and so on, Passive House only focuses on energy and ventilation.

Why We Use Dense-Packed Cellulose Insulation

Bensonwood's proprietary OBPlus Wall

A cross-section of Bensonwood’s cellulose-filled OBPlus Wall®.

Many have asked us why we use dense-packed cellulose insulation in our OBPlus Wall® panels, roofs and some ceilings and floors. Here are some of the cellulose advantages in our “Montage Building” system:

  • Our cellulose insulation is made from recycled newspapers treated with a natural mineral borate to give it a Class A fire rating as well as resistance to mold and pests.
  • The dry cellulose is blown into all the framing cavities at a settle-proof density (dense-packed), filling any shape with a continuous thermal insulation layer. The blowing process compresses the cellulose to a density of between 3 and 4 lbs/cu.ft. In addition to preventing any settling of the material, the dense-packed cellulose also cuts down convection that can occur around batt type insulation and in low-density blown fiberglass, particularly in colder temperatures.
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Cellulose being blown into a Bensonwood wall panel.

  • Dense-packed cellulose blocks air movement better than fiberglass batts. While sprayfoam also seals the enclosure against air infiltration well, its rigid consistency when cured may allow it to crack as framing members around the insulation dry and move over time. Cellulose has the flexibility to allow for such movement without resulting gaps.
  • Similar to wood fiber, paper cellulose fiber manages moisture well, taking in and releasing the moisture effectively. As a result, indoor relative humidity is much more even due to the hygroscopic buffering capabilities of the cellulose insulation. This is in contrast to the hydrophobic characteristics of fiberglass and foam insulations, which lack this capability and can cause a home’s interior to experience significant swings in humidity when weather changes. So, with its tremendous insulating and moisture management characteristics, cellulose helps to buffer temperature and humidity extremes.
  • While foam insulation has a slightly higher R-Value per inch, cellulose takes less energy to manufacture than any other insulation material. This embodied energy includes the total energy required to transport the raw materials, then manufacture and distribute the finished product. Fiberglass has up to 10 times more embodied energy than cellulose and foam products have as much as 64 times more.
  • Cellulose insulation is one of the greenest building products, having the highest level of recycled content in the insulation industry—as much as 85%. Fiberglass has a maximum of 40% recycled content and foam products little or none.
  • Cellulose sequesters carbon in a building’s components instead of releasing it into the environment. Cellulose insulation is made from recycled paper that might otherwise end up in landfills, releasing methane as it decomposes, or be burned, releasing CO2. This sequestration results in a positive carbon balance which helps the efforts to lower the material’s impact on climate change.
  • Cellulose insulation is produced regionally, employing local recycling programs and independent recyclers.
  • While all insulation provides sound reduction, cellulose has approximately three times the density of fiberglass as well as fibrous consistency, delivering enhanced sound dampening.

For more details on cellulose insulation, visit http://www.nationalfiber.com/cel-Pak.htm or http://cellulose.org/GreenestInsulation/.

What dense-packed cellulose looks like inside a wall.

What dense-packed cellulose looks like inside a wall.

Five Star Rating for Unity Home

We have received some fantastic news about the exceptional performance of our Unity Homes.

Rear Exterior of Vermont Xyla (Photos taken May 2013, Landscaping not complete)

Rear Exterior of Vermont Xyla. This home received a 5 Star Plus Certification for excellence in energy efficiency, is 56% more energy efficient than a home built to current code and 86% more efficient than the average American home. (Photos taken May 2013, Landscaping not complete)

We recently completed our first Unity Home, a Xyla in southern Vermont.  The home was tested by Efficiency Vermont for compliance with the Vermont Residential Building Energy Standard (VT-RBES). The 2,376 sq. ft. home with conditioned walk out basement achieved a Home Energy Rating System (HERS) score of 44, receiving a 5 Star Plus Certification for excellence in energy efficiency.

So what does that mean to a home buyer?

It means this home is 56% more energy efficient than a home built to current code and 86% more efficient than the average American home.  

This home also tested at 0.51 ACH50!  This number is so extraordinarily low that it surpasses the Passive House standard of 0.6 ACH50.

So you don’t have to take our word for it – the numbers show our Unity Homes continue to exceed the energy performance of other homes built to code.

Unity Home Xyla – Day 1

Job Captain Tobey Wandzy shows how quickly walkout walls, the first floor, timber ridge wall and exterior walls are assembled on-site on Day 1 on-site with the first Unity Home from Bensonwood.

The mission of Unity Homes is to improve the quality of lives by creating homes that are healthycomfortablesolid, and frugal, as well as beautiful.

We believe these attributes must be in place to achieve a home’s noblest purpose, which is to shelter and enrich your most important assets — your family, your friends, and the precious days of your life.

This home is a Xyla being built in Vermont. (www.unityhomes.com)

 

Xyla Exterior Front