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 Homes Outperform Other High Performance Homes

There are several key differentiators between our new Unity Homes and other standard homes built to code on the market, including the design, adaptability, Open-Built processes, off-site construction and prefabricated building. But anyone can SAY their homes are better. We’re backing it up with actual building science.

Recently Bensonwood Assistant Project Manager and Energy Analyst, Rheannon DeMond, who studied Architecture and Building Science in college, produced a Building Shell and Energy Consumption Comparison based on a Unity Home plan compared to other shells that can be found in the industry.

Unity Homes Annual Heating Cost Comparison

Unity Homes Annual Heating Cost Comparison

You can read the full two-page report here but to sum it up: Unity Homes outperform several of what the industry considers to be well-built, high performing homes – in a number of heat and energy categories. And keep in mind this is a standard Unity Home.

The Building Shell and Energy Comparison uses the Varm 113 Building Shell, and compares it to the Average New England Home, 2003 IECC Home, 2009 IECC home, 2012 IECC Home and an Advanced Thermal package.

Varm 113

Varm 113

The Baseline Unity Home consumes less energy than all other code building shells modeled, and only uses fractions more than the Advanced Thermal Package that has been used to achieve Passive House Standards in the New England area. The Energy Comparison confirms the benefits of heating with an Air Source Heat Pump, which results in an estimated 50% reduction in Annual Heating Costs. Lastly it reveals the predicted payback period for Solar Electric Systems over a thirty year period, while emphasizing the importance of a solid thermal envelope and air tight building shell.

To produce the Energy Comparison, Rheannon created a complete Energy Model of the Baseline Varm 113 home if it was situated in Portland, ME. After she obtained all of the performance numbers for that Building Shell, she used the same building footprint and location to model different versions of the International Energy Code Shell Specifications. Once she had modeled the performance numbers for all of the building shells she graphed the information to show how a Baseline Unity Home compares to the rest of the industry.

The numbers are impressive, and we continue to adapt and improve the design and performance of these homes. We’re on a mission with Unity Homes. Join us – sign up to receive Unity and Bensonwood news.

New Tools for Calculating Energy Usage in Net Zero Homes

Over the years at Bensonwood we’ve designed and built a number of LEED certified, Net-Zero homes and commercial buildings, but our team never stops in our quest to learn more, and deliver new and better design/build methods to the benefit of our clients, our world and our structures.

(Some noteworthy projects: Unity House which partially informed and inspired our new Unity Homes brand, the Net-Zero Coast Maine Botanical Gardens, and Burr and Burton Academy* which we recently blogged about).Rheannon DeMond

Bensonwood Assistant Project Manager Rheannon DeMond recently completed the Net Zero Energy Homes 10 week course as part of the NESEA Building Energy Masters Series that covered every aspect of designing a Net Zero Energy Home.  Rheannon has a background in building energy performance but was looking to further educate herself on the necessary calculations, systems and technologies that it takes to design a home for Net Zero Energy use.

(Read a post by Marc Rosenbaum who taught the course, on his Thriving on Low Carbon blog).

“What the company and myself got out of this course was a set of excellent calculation tools to make estimating all aspects of energy usage much easier.  We are now capable of estimating the total energy usage for a home in the North East, and the size of the Photovoltaic array that can handle those loads to make a home Net Zero capable.  The tools will also allow us to analyze current designs to show home owners the advantages and disadvantages of certain systems and orientations.  As a company that is always striving to be more efficient, this course has given us the additional information and tools to allow us to better design homes that will continue to save our clients money and reduce their impact on the environment.”

Please join us in congratulating Rheannon on completing the course.  Her expanded knowledge will benefit both Bensonwood and our clients!

*Note: Burr and Burton Academy’s Mountain Campus academic building was designed/built to achieve Net-Zero energy status and LEED Platinum certification but has not yet been certified.

Burr and Burton Academy

A view of the Burr and Burton Mountain Campus Academic Building as you approach from the road.

A view of the Burr and Burton Mountain Campus Academic Building as you approach from the road.

At Bensonwood we’re proud of our nearly 40 year history as the premier designer/builder of energy-efficient timber frame, hybrid, and other high-performance homes.

But we have also built a strong reputation for designing and building LEED certified, energy efficient and architecturally striking commercial buildings and specialty structures.

Recently, Bensonwood Lead Architect Randall Walter and other members of our architecture and engineering team designed the Burr and Burton Mountain Campus Academic Building.

Dedicated on August 23, 2012 in time for the opening of the school’s fall semester, the building is designed to be a living classroom with a goal of achieving LEED Platinum designation and Net-Zero energy status.

BBA Heater

The masonry heater is a focal point within the “Clearing” in the Mountain Campus Academic Building

Randall worked closely with the Burr and Burton team to ensure that the building not only fit into the natural surroundings of the site but truly became part of the learning experience for students, blending scientific architecture with artistic abstraction. Design features include ceilings inspired by the structure of the underside of a leaf, a skylight that casts light on the native Vermont slate clad masonry heater, between two reclaimed oak trees primary walls splayed at 14.5 degrees, celebrating the variation between true north and magnetic north in southern Vermont.

In keeping with typical Bensonwood design and construction practices, locally sourced materials where used wherever possible.

Speaking at the dedication ceremony Randall noted that a quote by Winston Churchill inspired the design – “We shape our buildings; thereafter they shape us.”

Below Randall has provided additional information on some of the features of the building:


  • Primary building area: 4000 square feet
  • Total building including overhangs: 6200 square feet

Building Materials

  • Marvin Ultimate clad Triple glazed windows and doors (R-5)
  • Cellulose insulated walls (R-35) and roof (R-60)
  • Red Oak – log posts from Alstead, NH & BBA campus
  • Nordic-Lam – engineered timbers – Canadian black spruce
  • Eastern white pine – rafters & ceiling boards
  • White and red pine wall boards (red pine from BBA campus)
  • Hemlock – rough sawn, random width siding from NH and VT
  • Western cedars – exterior posts and beams
  • Sliding barn doors – reclaimed local barn board, oak frames
  • VT sourced maple benches and window sills
  • VT Shadow Grey slate tile
  • VT Verde Green brushed marble counters and hearth

Interior and Exterior Finishes

  • Vermont Natural Coatings – whey based finish – used on all wood and concrete surfaces
  • All finishes have low or no Volatile Organic Compounds (VOCs)


  • Wood burning masonry heater
  • Air-source heat pumps
  • Energy Recovery Ventilators for fresh air
  • Photovoltaic arrays (Sept/Oct install) to achieve Zero net energy
  • All plumbing fixtures exceed EPA water sense standards
  • Preliminary blower door test below Passiv standards for air infiltration (495cfm@ACH50)

Construction Schedule

  • Foundation installed November 2011
  • Prefabrication offsite over winter
  • Site access reopened April 2012
  • Delivery of prefabricated parts and assembly begins May 2012
  • Building completed in 4 months
  • Waste management plan exceeded LEED requirements – near 93% waste diversion
  • Anticipated LEED points 82-83 (Platinum threshold is 80)

Unity Home – Xyla Day 3


In this second video, Job Captain Tobey Wandzy shows how quickly and efficiently our team was able to assemble a weather tight shell with siding and windows on our first Unity Home from Bensonwood.

In just three days the crew raised the home from foundation to fully enclosed, including a garage.

This home is a Xyla being built in Vermont. (

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. (


Xyla Exterior Front

First Unity Home: Part 1: In the Shop

Our first Unity Home is on-site this week. A five-person team will be raising a Xyla in a just a few days.

In this video (1 of 4 on our YouTube channel) Jay Lepple, Bensonwood’s Building Systems Team Leader demonstrates the features of a wall panel that was recently fabricated in our shop for this home.

This is video 1 of 4, with other videos demonstrating window and siding installation in shop, and the benefits of the Computer Aided Design (CAD) in our off-site construction process.

Walls in the shop

Wall panels packed and ready for wrapping before being trucked to the site