Habitat Forsyth Green Build, Winston-Salem, North Carolina
From Archiplanet
| Habitat Forsyth Green Build | |
| Designer | Peter Epermanis, Matthew Rodda—Calloway, Johnson, Moore and West, PA |
| Location | Winston-Salem, North Carolina, USA |
| Date | 10/3/2007 to n/a |
| Building Type | Small House |
| Climate | Subtropical |
| Context | Urban |
| Architectural Style | Vernacular |
| Builder | Habitat for Humanity of Forsyth County |
| Street Address | 1865 Willow Oak Way |
| Notes |
Contents |
[edit] Images
 insulated concrete forms |
 2X6 exterior wall |
 two story shell |
[edit] Discussion
| Building Details | |
| Area | 1,328 sf |
| Stories | 2 |
| Length | 44' |
| Width | 20' |
This first green build by the Habitat for Humanity of Forsyth County goes above and beyond the Energy Star homes they are currently building. The volunteer planning team chose to use the NC HealthyBuilt homes criteria to guide their work.
The team requested a 2 story plan from architects with Calloway, Johnson, Moore and West to reduce foundation and roofing costs, allowing for upgrades in other areas. At 880 s.f. on the first floor, the reduction is 27% over a typical Habitat floor plan for this area. The home is oriented along an east west axis with most of the fenestration on the south to reduce cooling needs in the summer and heating loads in the winter.
Below are some highlights of changes from Habitat Forsyth's normal building practices.
[edit] Siting
The planning team spent a lot of time looking at various lots which Habitat Forsyth owns. We used the following criteria to choose a site:
- a bus line within ¼ mile (promotes use of mass transportation)
- a community park within ½ mile (promotes a healthy and interactive community)
- a shopping and business district within 2 miles (reduces use of cars)
- a walkable community (sidewalks promote a healthy and interactive community)
- an east west orientation of the lot (allows for passive solar strategies in home design)
- a smaller lot size (higher densities)
Happily, new sites became available in the Glen Oaks neighborhood where Habitat was building already, and we found them to meet the majority of the above criteria.
[edit] Home design
- 2 story shotgun plan with simple 8 in 12 gable roof (except on hip roof on porch)
- 3 bedroom, 2 bath (1 on each floor)
- 8' ceilings except in first floor hallway where it is 7'4" to allow for ductwork
- passthru from kitchen to living area
- shed on back (west) side of home for additional unconditioned storage
[edit] Landscaping
- Partially edible landscaping includes fruit trees and berry bushes
- Raised-bed garden space for family to raise food and/or flowers
- Rain-water collection barrels to offset municipal water use for outdoor applications
[edit] Foundation & floor system
- slab on grade with deep footings
- to improve insulation at the slab edge, 1 course of insulated concrete forms (aka ICFs)
- perforated PVC pipe installed for future radon mitigation, if necessary (PVC is a problematic material—see USGBC's task group report—and we avoided it elsewhere, for example, in choosing a siding)
- 4" washed gravel, 1" styrofoam (R5) from Dow Corning and 6 mil polyethelene vapor barrier underneath 4" concrete slab with 25% fly ash
[edit] Exterior wall system
(from exterior to interior)
- LP SmartSide lap siding
- Dupont Tyvek to prevent water and air penetration
- Dow Corning donates 1" styrofoam (R5)
- 2 X 6 at 24" on center to allow for increased insulation and to reduce material usage
- 2" Dow Corning closed cell polyurethane foamed-in-place insulation (R12) (installation labor generously provided by Homes by Hamrick)
- 3 1/2" spray celloluse (R7)
- since no oriented strand board (OSB) sheathing, 2' or 4' wide inset shear panels at corners (see impact resistance of advanced framed wall systems)
- some advanced framing techniques like drywall clips at corners, 2 stud corners
[edit] Roof
- 2' overhang
- raised heel trusses
- galvalume metal roofing with solar reflectance index (SRI) greater than .50
- blown cellulose insulation (minimum R42)
[edit] HVAC
Rheem 13 SEER heat pump with variable speed air handler boosting the SEER to 14 btu/watt. The HSPF is 9.00 btu/watt with a 5 kw auxiliary heater installed in the air handler.
[edit] Water conservation
Faucets will have aerators which restrict water flow. We will install either dual flush or high efficiency toilets which score well on the Maximum Performance (MaP) toilet fixture test.
[edit] Interior finishes
- polished concrete - Decorative Concrete Resurfacing donated services for the entry, bath and kitchen
- interior plywood - Pure Bond Formaldehyde-free, FSC Certified, hardwood plywood donated by Columbia Forest Products
- interior paint - lower VOC paint donated by Valspar
