Project Subtitle:
Project Description:
This home was built with the intent to be environmentally sound, but at the same time taking advantage of the beautiful surroundings of this lot near the Shenendoah Mountains. The house was oriented to allow outstanding views from the rear facing southern exposure windows. The home was highly insulated, utilizes geothermal HVAC and a 10.26 KW solar array to minimize net energy consumption.
Key features of the home are as follows:
- Well Insulated (R-21 in walls and R-50 in the cieilings), band joints and joints sealed with closed cell foam
- Utlizes a Waterfurance Series 5 geothermal heat pum for heating and cooling
- A wine cellar with takes advantage of a combination of passive cooling plus trim coolling and humidity control via a water to water hiller run off of the geothermal system
- Home is oriented to obtain passive benefits. Energy Star rated windows and overhangs desinged to minimize summer heat gain
- LED Lighting and Energy Star Appliances
- 10.26 KW solar array installed on barn to provide sufficent power to make the home a close to a net zero home. Note: Virginia law does not allow indivisuals produce more solar power than their useage.
https://tours.vahomepics.com/public/vtour/display/652780
Building Type Summary:
Address:
Elevation:
Lat. / Long.:
Location Type:
Köppen Climate Type:
Climate Region:
Solar Insolation:
Annual HDD :
Annual CDD:
HDD Base Temp:
CDD Base Temp:
Occupancy Type and Details:
Owner-occupied, 2 residents
Conditioned Floor Area:
Conditioned Building Volume:
Semiconditioned Floor Area:
Unconditioned Floor Area:
Multiple buildings?:
Total number of units in project (all buildings):
Total floor area of project (all buildings):
Historic?:
Site description:
Home is on an 8 acre lot about 1 mile from the Blue Ridge Parkway
Materials:
Landscaping utilizes native plantings
Energy Highlights:
Home uses Passive solar, geothermal HVAC, well insulated walls, Energy star windows and a photovolatic array for energy production.
HERS Index:
Annual renewable energy generated:
Electric Utility Company:
Electricity amount (imported from grid):
Electricity amount (credited or exported to grid):
Net electricity usage (purchased electricity):
Above grade wall assembly:
2x6 timber stud walls on 16 centers, 7/16 OSB sheathing and Tyvek wrapped. R-21 dense pack cellulose insulation full cavity, Joist ends and bands foamed.
Flat attic assembly:
blown in cellulose insulation in flat attic surfaces
Cathedral ceiling assembly:
Fiberglass batt insulation in cathedral ceiling spaces
Space heating - Manufacturer & Model:
Space heating - capacity:
Space cooling - Manufacturer & Model:
Space cooling - capacity:
Process:
The design process was managed by the owners of the property based on our own independent research and advise of our contractors. We did not pay external consultants to design this project.
Design for Adaptability:
The design and construction of the project utilized readily available materials. This proves that building a zero energy home does not require unique materials or special design expertise.
Finances Description:
The net cost of the energy upgrades are as follows:
10.26 KW Solar Array - $29,500
Geothermal Heat pump upgrade - $20,000
Upgrade to 2 x 6 Framing - $2,500
Energy Recovery Ventilator $2,500
Extra insulation above code - $2,000
Energy star Windows - $1,500
Additional Heating Zone - $1,500
LED lighting - $500
Credits below only count the electric savings associated with the solar electric generation. It is likely that the total electric power consumption savings are much more as the HVAC costs asre significantly lowered from the use of the geothermal heat pump, extra insulation, passive solar gain anf LED lighting. I estimate that if these savings are added in that the net electric savings are ~3000/year. The overall return on Investment for this project assuming a 25 year evlauation period is in the range of 6 - 8%/yr.
Gross Cost of Renewable Energy System:
Value of Tax Credits for renewable energy systems:
Net Cost of renewable energy systems:
Federal incentives:
30% Federal tax credit for 10.26 KW solar array and Geothermal Heat pump.
Annual Electric Savings:
Special architectural measures:
The home was oriented with south south west rear exposure and extensive energy efficient windows. The goal was to utilize passive solar design with other efficient designs to enable a zero energy home. A solar array was placed on a south facing barn roof.
Above grade wall R-value:
Flat attic R-value:
Cathedral ceiling R-value:
Average window U-factor:
Solar Heat Gain Coefficient:
Visible Light Transmittance:
Project Photos:
Number of Bathrooms:
Scope Description:
New home was constructed to be a near zero energy building. The energy desing was largely directed by the home owner without the use of external consultants.
Site conditions:
Renewable Energy Sources:
Other Purchased Fuels Description:
Propane fire place and gas stove for cooking
Summary of enclosure strategy/description:
2x6 timber stud walls on 16 centers, 7/16 OSB sheathing and Tyvex wrapped. Tight insulation as described below
Roof Assembly:
30 # felt under asphalt architectural shingles. Continuous Soffit vents at eaves with ridge vent on shingles, Blown in cellulose on flat ceiling surfaces as noted above
Window Description:
Jeld-Wen Energy Star Rated windows