The Whitchurch PHIUS+ Passive House in Middlesex

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Barb & Greg Whitchurch built this right-sized home for Greg's elderly parents, Ev & Norm; so that instead of being in an assisted living space in Akron, OH, they're here in beautiful VT with their kin.

The "Cottage" is 24x24x24 inside (28x28x28 outside) with a poured concrete full basement plus two floors. The snow stays atop the  1/2 in 12 roof where it is insulation, rather than atop the flower beds where it would remain until April. The skeleton is post & beam and the 16" cellulose DP curtain walls are spaced outside the timber frame 2" so that the frame seems to float inside the house, independent of the thermal envelope. The cladding is UV-protected local, rough-cut white cedar T&G; the inside is the same except uncoated, planed & V-grooved. The SW corner window assy. is 13'H x 21'W & protected by a removable summer shading device. The inside finishes are rustic: wood, 3" live-edge pine slabs for some counters & sills, cherry accents, cedar cabinets.

The building provides all necessary functions on the first floor - anticipating a time when movement between floors will be difficult - & the 2-story stairway cut-out is sized for a home elevator. The 1st floor is also exactly level with the main floor of the main house - to which it is connected by a protected, but unheated, breezeway.

Because the Cottage has a "hot" roof, its PV and thermal panels are mounted on the main house next door.  The cottage's DHW tank has electric backup and resides w/in an R-56 superinsulated enclosure. The CERV, Conditioning Energy Recovery Ventilator, provides fresh air, cooling & heating at high volume only when needed according to user-set temperature, CO2 & VOC limits; is controllable through the Internet; has no refrigeration lines or external components; & resides entirely inside the building for increased efficiency.

Other information on this house: Passive House Institute U.S. listing475 High Performance Bldg. Supply; & Journal of light Construction(9/14); 7-DaysWCAX TV (the photos); Green Energy TimesJournal of light Construction(3/15) & online photo album.  See also this site's "Presentations" pg.: Miksic 2/14 & 10/14; Ruth-Davis 10/14.  In the winter of '15-'16 a bubble of interest in our unvented flat roof arose again: this 475 blog refers to the GBA posting a week earlier; (Germany just happened to approve this design here almost simultaneously); the March Journal of Light Construction weighed in on the issue ("Unvented Flat Roofs: Theory Meets Practice" by Ted Cushman, pg. 49); &, in turn, 475 blogged that piece here (while also noting that Germany has approved the design now: here.

PHAUSVtProjectSubmittalForm-Middlesex P1010777-001P10107231P1010702-001P1020619-001

This home is also asking two building science questions about the envelope: (1) Can a full-depth 16" DPC wall system with a variable-perm, vapor-open inside membrane & a vapor-open outside membrane be airtight and handle moisture properly over the long term? (2) Can a flat, unvented EPDM roof system (vapor-closed surface, so vapor drive limited to the inside) with full-depth 22" DPC insulation & a variable-perm, vapor-open inside membrane (cathedral ceiling) handle moisture properly in this climate?  The designers have embedded dozens of temp., RH, & moisture sensors of two different types & from three different mfrs. at all different depths & on all the different materials enclosed by these systems (pix here).  Several engineering firms & some suppliers are watching for results over the next few years.  If you are interested in sharing these data, contact This email address is being protected from spambots. You need JavaScript enabled to view it..

This Home Received the
Vermont's Greenest 2015 Residential Building Award
Vermont Green Building Network
as well as their
Net Zero 2015 Residential Building Award

VGBN Poster