Kraus-Fabel Retrofit
Net Zero Renovation of Small Duplex Home in Cohousing Community
Completion
Completion date 11/23/2010
Occupancy
Owner-occupied, 3 full-time occupants, typical residential occupancy.
Days per year Building is fully occupied: 365
Scope
Existing home. Air sealing, reduction of plug loads, replacement of propane-fired heating and hot water with electrical, addition of PV.
Type of Construction
Retrofit
Number of buildings
1
Floor area of each building
1,200
Bedrooms
3
Bathrooms
1.0
Stories
2
Conditioned Building Volume
13,000 cu ft
Conditioned Floor Area
1,200 sq ft
Semiconditioned Floor Area
396 sq ft
Location and Climate Details
One side of residential duplex
Address
120 Pulpit Hill Road
Amherst, MA 01002
United States
Location Type
Suburaban
Climate Region
Zone 5
Köppen Climate Type
Dfb
Lat. / Long.
POINT (-72.5236273 42.4174055)
Elevation
250 ft
Solar Insolation
3.57 kwh/m2/day
Annual CDD and Base Temp
214 | 70 deg F
Annual HDD and Base Temp
6,400 in 2012, 6,700 average | 65 deg F
Site
Site conditions: preexisting structure(s)
Site description: Retrofit of existing duplex unit (one side of duplex only) within 32-unit cohousing community.
Materials and Design Strategy
Materials: It was a retrofit, with a minimum of new materials. The original construction in 1994 prioritized for sustainable and healthful materials, systems and design. Retrofit involved air sealing; a new, more efficient refrigerator; installation of HRV to replace exhaust-only ventilation; ASHPs to replace propane boiler; super-insulated water tank to back up existing solar hot water; installation of PV.
Special architectural measures: The existing home was sun-tempered, well-insulated, and reasonably tightly built. The retrofit included targeted air sealing to improve performance. I think we need to go back and verify the air sealing, as I have reason to suspect that the mechanical installation may have resulted in breaches in the air barrier. (In spite of this, the home was net energy producing in the first year.)
LCA Description: No.
Indoor Environment Description: Heat recovery ventilation replaced exhaust-only ventilation. The original materials were specified for indoor health, including white pine floors and cabinetry with water-based finish.
Completion
Occupancy
Owner-occupied, 3 full-time occupants, typical residential occupancy.
Scope
Existing home. Air sealing, reduction of plug loads, replacement of propane-fired heating and hot water with electrical, addition of PV.
| Type of Construction | Retrofit |
|---|---|
| Number of buildings | 1 |
| Floor area of each building | 1,200 |
| Bedrooms | 3 |
| Bathrooms | 1.0 |
| Stories | 2 |
| Conditioned Building Volume | 13,000 cu ft |
| Conditioned Floor Area | 1,200 sq ft |
| Semiconditioned Floor Area | 396 sq ft |
Location and Climate Details
One side of residential duplex
| Address |
120 Pulpit Hill Road Amherst, MA 01002
United States |
|---|---|
| Location Type | Suburaban |
| Climate Region | Zone 5 |
| Köppen Climate Type | Dfb |
| Lat. / Long. | POINT (-72.5236273 42.4174055) |
| Elevation | 250 ft |
| Solar Insolation | 3.57 kwh/m2/day |
| Annual CDD and Base Temp | 214 | 70 deg F |
| Annual HDD and Base Temp | 6,400 in 2012, 6,700 average | 65 deg F |
Site
Retrofit of existing duplex unit (one side of duplex only) within 32-unit cohousing community.
Materials and Design Strategy
It was a retrofit, with a minimum of new materials. The original construction in 1994 prioritized for sustainable and healthful materials, systems and design. Retrofit involved air sealing; a new, more efficient refrigerator; installation of HRV to replace exhaust-only ventilation; ASHPs to replace propane boiler; super-insulated water tank to back up existing solar hot water; installation of PV.
The existing home was sun-tempered, well-insulated, and reasonably tightly built. The retrofit included targeted air sealing to improve performance. I think we need to go back and verify the air sealing, as I have reason to suspect that the mechanical installation may have resulted in breaches in the air barrier. (In spite of this, the home was net energy producing in the first year.)
No.