Elm Place, located in the heart of Milton, opened in March 2017 and features 30 affordable, one-bedroom apartments for adults 55 and older. Two apartments are fully ADA accessible, and all apartments are adaptable.
Vermont’s first multi-family building certified to Passive House standards is designed and constructed to use approximately 65% less energy than a standard home built today. This senior living facility achieves Passive House standards through the use of energy-efficient windows and doors, insulation, and improved air sealing. Extensive review and oversight were given at each phase of construction to ensure products and installation meet or exceed the specified standards.
Cathedral Square Corporation is a non-profit developer providing affordable, senior housing with common space and support services to allow seniors to live independently as long as possible. The program was to develop 30 affordable residences on a long thin, seemingly unpromising, suburban site. However this would be the first project in the Town of Milton's newly designated downtown, pedestrian friendly core, so we had the opportunity to set the tone.
Design Challenges
Realize PH in cold Vermont for no extra money on a long, narrow site not square to street site. Create a street friendly, warm and welcoming place on this somewhat odd site. Deal with some unexpected geotechnical challenges that increased costs and figure out how to thermally break the steel and concrete garage structure from the envelope. Trash chutes and dryers.
Design Solutions - Site
For both PH and budget we pursued simplicity and took inspiration from a cathedral: A repetitive, boxlike, cellular structure (covered parking and residences) with a few functions (common spaces) pulled out from box for special treatment.
We jogged the long box to reduce its visual scale on site and increase visitor parking.
Common spaces on south side to address street, including front porch. Covered entry and parking access on west side. East side includes protected courtyard, raised garden planters and social spaces. North end includes walking loop, fruit trees, pergola and bocce court.
Design Solutions - Envelope
Although Vermont is full of small builders doing energy efficient single family homes this is somewhat lacking on larger scale construction. We stayed with basic wood studs, zip air barrier and exterior insulation. The inherent surface to volume efficiency of a large structure allowed lower R values that were much less than on single family.
We chose to exceed the standard with basic envelope knowing that there were some areas where we would have to take a hit: No one making trash chutes is interested in air tightness. There were no real condensing commercial dryers. The fire rated exterior door was not as tight as they say. A pleasant surprise was that the U .13 uPVC tilt/turn windows were cost competitive.
What would & wouldn't you do again? What are some ideas that worked well for this project?
The envelope seems perfect. Residents are not enamored of the tilt/turn windows.
Our steel column thermal break is a winner. The thermal pads are not a perfect break and it is magnified when four beams intersect a column. Our engineer had the idea to cut the column short in the middle of the ceiling thermal blanket, add the thermal break and then add a short stub column on top of it so the intersecting beams are already beyond the thermal break.
We assume that commercial condensing dryers will come on line soon. In the meantime ducting fresh air directly into dryer with an interlock damper did a decent job.
What are some benefits to the building owner? How did you sell PH to the client?
The Owner provides heat and cooling in the rent and they are very sensitive to energy costs. Over the past few years they have been increasingly open to saving energy, comfort and healthy buildings. Therefore, they were totally open to this as long as it did not add cost and had a decent payback. The feedback they are receiving is that the buildings are more comfortable.
Case study source: https://multifamily.phius.org/case-study/elm-place-vt
Multifamily Building - Milton, Vermont - July 2017
Architect: Duncan Wisniewski Architects
Builder: ReArch Company
CPHC: Chris West, Eco Houses of VT
MEP: Engineering Services of Vermont
Structural: Hardy Structural Engineering
PHIUS+ Rater: Karen Bushey, Efficiency Vermont
# of Units: 30
Size: 29,340 sf gross, 27,690 TFA + 10,191 sf garage
Heating: Mitsubishi Hyper Heat plus electric resistance
Ventilation: Daikin ERU Renewaire HE 1.5x
EUI: 20.2 kBTU/sf/yr
Air Tightness: 0.7
Total Cost: $5,391,000 base bid = $183 sf for 29,340 gross sf conditioned space. The 10,170 sf of open parking garage is amortized over the gross sf area. Because the contingency was hardly used the Owner elected multiple upgrades including an emergency generator, smoking shelter, landscaping, pergola and bocce court that brought final cost to $190 sf.
Certifications: PHIUS+ 2015
Awards: 2017 PHIUS: Best Overall Project, Best Senior Housing Project, Honorable Mention for Affordable Housing