Barb and Greg Whitchurch built this right-sized home for his elderly parents. Now, instead of residing in assisted living in Ohio, they're here in beautiful Vermont with their kin.
The Cottage is 24'x24'x24' inside (28'x28'x28' outside) with a poured concrete full basement plus two floors. The snow stays atop the ½-in-12 roof where it provides insulation, rather than on top of the flower beds where it would remain until April - or May! The skeleton is post and beam, and the 16" cellulose dense pack curtain walls are shimmed 2” outside the timber frame so that the frame seems to float inside the house, independent of the thermal envelope - which it wears like a sweater. The cladding is UV-protected local, rough-cut white cedar T&G; the inside is the same, except uncoated, planed and V-grooved. The SW corner window assembly is 13'H x 21'W and protected by a removable summer shading device. The inside finishes are rustic: wood, 3"-thick live-edge pine slabs for some counters and sills, cherry accents, and cedar cabinets.
The building provides all necessary functions on the first floor - anticipating a time when movement between floors will be difficult - and the two-story stairway cut-out is sized for a home elevator. The first floor is also exactly level with the main floor of the main house - to which it is connected by a protected, but unconditioned, breezeway.
Because the PH Cottage has a flat unvented "hot" roof assembly, its PV and thermal panels are mounted on the main house next door. Its DHW tank resides within a superinsulated (R-56) enclosure. The Conditioning Energy Recovery Ventilator (CERV) provides high CFM fresh air, cooling, and heating, but only when needed - according to user-set temperature, CO2 and VOC limits. It is controllable over the Internet; has no refrigeration lines or external components, and resides entirely inside the building for increased efficiency and freedom from icing in the winter.
From the beginning, the entire project team committed to socially and ecologically responsible practices. The home was constructed with locally harvested, sawn and milled sustainable woods; kiln drying was done locally in a wood-fired kiln; all hidden members were left rough cut. We used no plywood except for window boxes; no OSB except in the TJI's; no foam above ground and only recyclable EPS below. We re-purposed used materials (particularly foams) from tear-downs and carefully recycled all waste. Construction scraps were sorted, stored and heavily reused. Our adhesives were low VOC, low hydrocarbon, mostly acrylic; the frame was oiled with Land Ark. There were no bonfires: burnable scraps went to several firewood and kindling piles.
Single family home - Middlesex, VT - August 2014
Construction: Timberframe w/ curtain wall
Gross sq.ft.: 1712 (vol. 13824 cf)
Energy Monitoring: OutBack; eMonitor
Envelope Sensors: Delmhorst, Build Natural, PowerWise
HDD Ratio: 1.02
Total Annual Energy: 15,010.8 kBTU
Building EUI: 8.8 kBTU/sf/yr
Renewable Energy EUI: 10.8 kBTU/sf/yr
Weather normalized: 8.6 kBTU/sf/yr
HERS Score: 5 (without renewables)
Energy Star: 5+
Air Tightness: 0.28 ACH50
Heat/Cool/Vent: CERV 5 kBTU heat pump
Annual Heating Demand: 3.59 kBTU/sf/yr
Heating Load: 3.16 kBTU/sf/hr
Primary Energy: 29 kBTU/sf/yr
Awards: Efficiency Vermont Best of the Best in Residential Innovation, 2015