Kane Family Residence
The inspiration for this house came from three sources: Marc Rosenbaum (especially the Hanover NH house), Carter Scott (Transformations Inc. and the Coppersmith Way development in Townsend MA) and Sarah Susanka’s book – The Not So Big House. I was introduced to all three by the NESEA Building Energy conferences.
The motivation for this house was the desire to live comfortably in a way that minimized our contribution to global warming. I also wanted to show that not all new homes had to be big, ugly, and inefficient. Lastly, I wanted to employ the Evergreen Solar panels that I had spent the last 14 years helping to manufacture right here in Massachusetts.
I was very fortunate to work with Carter Scott and Jeff Richards of Transformations Inc. and Rick Gilles of Barnraisers Inc. during the design phase of the project. They did a great job of taking my rough sketches of a one and a half story Maine farmhouse and turning them into a set of construction drawings that incorporated many of the features Carter employed in the Coppersmith Way homes.
I decided to manage the construction phase myself and put in a lot of sweat equity to save money. I was fortunate again to hire Robert Austin of RT Construction to handle the framing and siding. He did a first class job.
Nothing about this house is really new or radical. It uses standard materials and construction practices that are becoming common. It cost about the same to build as a typical home. It’s success lies in the attention to the details – both architectural and energy wise.
Unlike most zero energy homes being built today, this house uses a solar thermal system to satisfy most of its heat and hot water needs. Although it cost more than a pure PV design, the benefits of this system are that it enables the use of radiant floor heating (which is very efficient, comfortable, quiet and draft free), it’s capable of collecting an amazing amount of energy on a sunny day and it enables the use of a simple instantaneous electric water heater for inline backup.The drainback design eliminates the need for antifreeze, eliminates stagnation problems in the summer and is basically maintenance free. Judging by the last years real world results, it worked out very well.
What I think is great about this house is as follows:
1. Net positive performance – no electric bills or fuel bills
2. It’s architecturally pleasing
3. It ‘s the right size – not too big, not too small
4. It’s very pleasant to live in – warm floors, bright sunlit spaces,cool in the summer, warm in the winter, quiet, uniform temperature throughout, comfortable humidity levels in winter
5. Everyone likes the cozy bench seating at the dining table
6. The kitchen layout is great and the pantry keeps it uncluttered
7. The interior windows above the sliding door bring amazing natural light to the second floor bathroom and master bedroom and allow for natural air circulation
8.The vestibule entry with the stained glass window is as practical as it is beautiful.
9. The floor grate by the front door is great for preventing dirt from getting tracked inside
10. The wide windowsills are great for plants
Quick Facts
General
| Location | 149 Ellis Street Westwood, MA02090 United States |
| Building Type | single-family residence |
| Project Type | Zero Energy |
| Basis of Performance Claim | Verified, |
| Bedrooms | 3 |
| Conditioned Floor Area | 1 998 |
Energy Summary
| Energy Data Type | Measured, |
| Renewable Energy System Type(s) | Photovoltaics, |
| Ratings | |
| Annual renewable energy generated | 7 074 |
Envelope and Mechanicals
| Subslab assembly | 2” XPS Foamular R10 |
| Foundation wall assembly | 3.5” closed cell polyurethane foam, 2.5” polyisocyanurate R36 |
| Above grade wall assembly | Double 2x4 wall construction – very little thermal bridging |
| Door Assembly | Steel, insulated U.16 |
| Air Changes per hour, ACH50 | 0.60 |
Project Team:
Other Team Members:
Peter Kane
Carter Scott, Transformations Inc
Jeff Richards, Transformations Inc
Rick Gilles, Barnraisers Inc
Robert Austin, RT Construction
Ratings:
Awards:
Completion
Completion Date:
Scope
| Type of Construction | New, |
| Number of buildings | 1 |
| Floor area of each building | 1 998 |
| Bedrooms | 3 |
| Stories | |
| Conditioned Building Volume | |
| Conditioned Floor Area | 1 998 |
Location and Climate Details
single-family residence
| Address | 149 Ellis Street Westwood, MA02090 United States |
| Location Type | Suburaban |
| Climate Region | Zone 5 |
| Köppen Climate Type | Dfb |
| Lat. / Long. | POINT (-71.217073 42.2137839) |
| Elevation | 226 |
| Solar Insolation | 3.82 kWh/m2/day |
| Annual CDD and Base Temp | 710 | 65 F |
| Annual HDD and Base Temp | 6428 | 65 F |
Site
Site Conditions:
Site Description:
Monthly Energy Data and Utilities
Energy Data Type: Verified,
Electric Utility: NSTAR
Gas Utility:
Renewables and Energy Balance
Renewable Energy Sources:Renewable energy is generated within the building footprint (e.g. solar PV on the roof),
Renewable Energy System Description & Details: 5.88 kW, 28 Evergreen Solar ESA210 Fa-3 modules Estimated annual production 6,500 kWh, actual annual production 7,399 kWh SolectriaPVI5300 grid tied inverter Revenue grade meter TTi Flat Jack roof mounts Unirac SolarMount rails Installation by Alteris - now Real Goods Solar
| Annual renewable energy generated | 7 074 |
| Annual Renewable Energy Generated Data Type | Measured, |
| Power Rating | |
| Renewable Energy System Type(s) | Photovoltaics, |
| Source of Annual Production Data | metered data |
Walls and Roof
| Subslab assembly | 2” XPS Foamular R10 |
| Subslab R-value | 10.00 |
| Slab edge assembly | |
| Slab edge R-value | |
| Foundation wall assembly | 3.5” closed cell polyurethane foam, 2.5” polyisocyanurate R36 |
| Foundation wall R-value | 36.00 |
| Above grade wall assembly | Double 2x4 wall construction – very little thermal bridging |
| Above grade wall R-value | 42.00 |
| Cathedral ceiling assembly | |
| Cathedral ceiling R-value |
Windows and Doors
Window Assembly:
Thermotech casement style, fiberglass, triple pane, argon filled, U value 0.19
Different glass with higher SHGC of .64 used on south side for more passive solar gain
No sloped glass
Double cell honeycomb shades
Door Assembly:
Steel, insulated U.16
| Average window U-factor | 0.19 |
| Door U-Factor | 0.16 |
| Door Area |
Mechanical Systems
| Space cooling - Manufacturer & Model | |
| Space heating - Manufacturer & Model | Roth ¾” radiant floor panels. One zone, six loops of 3/8 PEX tubing – in first floor only, TEKMAR tN2 House Control 400 outdoor reset, networked thermostats, Caleffi manifold, Taco 009 circulator pump, 1500 W electric fireplaces in each bedroom, rarely used, |
| Domestic hot water - Manufacturer & Model | Four (4’ x10’) Heliodyne Gobi flat plate collectors – 160 sq.ft. |
| Domestic hot water - capacity | 488 |
| Ventilation - Manufacturer & Model | Two Fantech SHR 1505 142 CFM air to air heat exchangers, Venmar Transition Tandem exterior vent, |
| Lighting Manufacturer and Model | 2700K LEDS and compact fluorescents used exclusively, |
| Lighting Efficiency | No lights are needed during the day, |
| Mechanical Equipment Installation Details and Comments | Solar hot water system: Radiant floor heat system (first floor only): Msc: |
Envelope
| Air Changes per hour, ACH50 | 0.60 |
| Air Changes per hour, CFM50 |
General Process
Design for Adaptability:
Software Tools
Software Tools:
General modeling information:
Lessons Learned
Outcome of Project Goals:
What I would do differently next time:
optimum value engineered framing
real time electricity use meter in kitchen
Discrepancies:
Rebates and Financial Incentives
| Federal incentives | |
| Local incentives | |
| State incentives | |
| Utility incentives | |
| Other incentives |