State-of-the-Art Sustainable New Mountain Home
Front Entrance towards “bridge”
Our overall strategy was to keep the short and long-term impacts of the construction and operation of the house to a minimum. We referred to many of the “green” scoring systems (such as LEED, GreenPoint, Passivehaus, and Living Building Challenge) to develop our own goals. To avoid some of the downsides of the scoring systems (so-called “point chasing”) we decided to only rate with GreenPoint and Energy Star. Our primary goals were (of equal importance):
·Energy efficiency (construction and operation)
·Human Health (occupants, builders and suppliers)
·Minimize material consumption impact
·Minimize or restore site impact (permaculture).
·Human factors (aesthetics matter!)
Ways in which we tried to meet those goals…
In Design (a brief list):
·Passive solar gain: East-West house orientation maximizes southern solar gain and daylight while minimizing western facade overheating.
·Maximum day-lighting using windows, overhangs and interior windows locations.
·Open floor plan for optimal air circulation.
·Universal design for ease of access for all abilities.
·“Scalable” house multi-zone floor plan and mechanical design allow house to be energy efficient for 2-9+ occupants.
·Integration of natural environment through green roof, living wall, greenhouse, screen porch, and creek.
·Water runoff management (and snow melt) re-infiltrated through trenches, bio-swales and drywells.
·Sealed basement is unconditioned yet integrated with house ventilation.
·Barn located and designed for maximum photovoltaic gain.
·Double-walls and I-Joist roofs for maximum insulation.
·Designed on a 2 ft grid to efficiently use framing materials.
·All electric, fossil-fuel free house (except for back-up generator).
·Advanced Framing Techniques (e.g. 24” OC studs and engineered wood)
·Airtight building using gaskets, embedded polyethylene air-barrier, high quality tape, spray foam, caulking and minimal, sealed penetrations.
·Super Insulation: Roof has closed-cell spray foam and sprayed Spider Fiberglass (R-70); double-walls of Spider fiberglass (R-44); Basement walls Spider Fiberglass and EPS foam boards (R-30); sub-slab insulation spray foam (R-20).
·Testing: Blower door, smoke test and infrared cameras to find flaws (final result: 1.1 ACH CFM50).
·High Efficiency Windows: Triple-pane, low-e coated glazing with thermal spacers made from FSC wood with aluminum exterior cladding.
·Integrated radon capture and venting system.
·Solar thermal system for heating and domestic hot water.
·Ground source heat pump for secondary, but primary heating source.
·Heat pump water heater for boosting DHW capacity.
·Central wood stove for high-efficiency, EPA certified auxiliary heating.
·No A/C system - passive cooling instead.
·Photovoltaic system grid-tied, 10.7 kW solar PV system on barn roof.
·High efficiency lighting (100% LED and CFL’s)
·All appliances are Energy Star rated.
·Whole house ventilation: Central HRV and Energy Star rated fans.
·Structured plumbing and regulated hot water recirculation pump.
·Low-flow toilets and showers: Watersense certified.
·Advanced control systems: to manage and monitor energy use.
·Reuse of site material: Felled trees used for interior finish, fencing, mulch, and firewood. Stone used for walls and paths. Topsoil re-used for landscaping.
·Use reclaimed materials: Almost all finish wood is reclaimed: exterior siding (both house and barn), flooring, interior walls and ceilings.
·Use recycled material: Metal siding, roof and I-beams are made from recycled US steel. Greenroof material from recycled sources.
·FSC wood: Used for all structural wood. (95+% of wood is FSC or reclaimed)
·Minimal use of “red-list” materials: such as PVC, urea-formaldehyde, polystyrene, drywall and copper.
·Low or No VOC paints, stains, caulking and adhesives. Clay paints and natural plaster on interior walls.
·Recycling waste: over 95% of all off-site waste (70% excluding organic matter) Even the recycling bins are recycled!
·Local sourcing of wood, stone, rock, concrete, soil, insulation, and interior finishes.
Designers, Vendors and Suppliers
Architecture: MWA, Inc. - Architecture and Engineering.
Contractor: Heller Construction, Inc.
Green consultant: Ann V. Edminster
Geotech engineers: Holdrege & Kull
Structural engineers: Gabbart & Woods
Ground Source Wells: Bruce McKay
Site Work: Al Pombo, Inc
Energy Systems: Bender Engineering
Photovoltaic: Solar Wind Works
Interior Design: Heller Construction, Inc., Katherine Elkins Rule , ASID and Patty Heller
Roofing system: Sierra Sage Roofing
Landscape Design: L+P Designworks
Landscaping: Tahoe “C” Company
Insulation: Sierra Insulation
Air-Seal Testing: Lake Tahoe Home Performance
Plumbing (heating): Craig Price
Plumbing (domestic water): MJ Berenbak Plumbing
Electrical and Controls: Squaw Valley Electric
Sheetrock and Plaster: Mudslingers
Living Wall: Habitat Horticulture
Metal Fabrication: Hunter Metal
Masonry: Ken Saling Masonry
On-site wood milling: Dan Borghi
Exterior wood siding: TrestleWood II and Picklewood from Trestlewood
Exterior metal siding: 22 Gauge, A606-4 steel sheets, 70% recycled content
Exterior cedar fascia, decking and fence posts: Milton Holsten Forest Products
Barn siding: Yankins Lumber
Structural lumber: (FSC and Engineered): Truckee Tahoe Lumber
Interior wood floor and paneling: Superior Hardwoods
Interior doors and front door: High Sierra Doors
Interior paints: Benjamin Moore Natura and Bioshield Clay Paints
Interior wood stains: Bioshield Aqua Resin with natural bees wax
Interior plaster: Stucco Italiano natural lime plaster
Roofing: A606-4 corrugated steel (“corten”), CertainTeed Landmark Pro 50 year asphalt shingles, IB RoofSystem membrane for flat decks.
Insulation: Johns Manville Corbond III Closed Cell Spray Foam, JM “Spider” blown fiberglass; EPS foam from Insulfoam.
Windows (and glass doors): Loewen; Green-house skylights from Crystalite.
Building gaskets: Conservation Technology for sill plates and windows
SIGA air-sealing tapes (Small Planet Workshop)
Polyethylene air-barrier: Tu-Tuf XF
Solar thermal system is Heliodyne Heliopak with collectors from GOBI
Ground source heat pumps: Geocomfort GWT048B, COP 3.1, Energy-Star
Heat pump water heater: GE Geospring Hybrid, 2.4 Energy Factor, Energy-Star
Barn hardware: Crown Industrial
Fireplace: Xtrodinair 44 Elite, 76,000 BTU, 2.5 gm/hr emmisions.
Generator: GE 30 KW, propane
Photovoltaic system is 42 AUO 255W modules with Enphase micro-inverters.
Ventilation system (HRV): Zehnder 550 (80% heat recovery at <1w/cfm) and Panasonic WhisperGreen fans.
Green roof system: XeroFlor
Control Systems: Lutron (for lights), Savant (A/V, Energy), Rehau/ENV (heating), Cyber-Rain (irrigation)