Rideau Passive House

Project Description

Redevelopment of an urban lot specially chosen for its solar orientation and views of Ottawa’s downtown over the Rideau River. Densification of an established neighbourhood on a site in close proximity to many services and amenities.

The building’s form was driven by the optimal urban site on which it was built – albeit a very small one. The two unit development rests on a 40’x 40’postage stamp parcel of land, adjoining a neighbourhood street with frequent bus service and a public space that overlooks the Rideau River.

Although the building is an unabashedly modern addition to a neighbourhood that prides itself on its architectural heritage, the materials used on the exterior are typical of its milieu: red clay brick, eastern white cedar, concrete, and steel. The flat roof, front porches and symmetry of the building are in keeping with the predominant typology on the street.

Living spaces are situated within the building so as to maximize southern views over lands protected from future development. Generous glazing is protected with 3’- 4’canopies and exterior roll-down shading. Tilt-n-turn doors and windows have insulated fiberglass frames supporting triple glazing (low E hard coat, argon filled, and thermal edge spacers).

Sleeping spaces lie closer to the ground, while storage, washrooms, and circulation are stacked on the north side of the building. A solid maple staircase with open risers facilitates the natural ventilation of spaces, from the walk out basement to the green roof access off of the third floor. An efficient dual core heat recovery ventilator with an electronically commutated motor provides continuous ventilation during the heating season.

Extensive use of closed-cell polyurethane spray foam provides high insulation levels in joist and stud cavities, on concrete foundation walls and below the basement slab. Thermal bridging through pre-engineered 2×6 wall panels and 14” roof/canopy joists is mitigated with layers of foil-faced polyisocyanurate rigid insulation. All wood to wood connections in the building are caulked and building envelope penetrations are sealed with foam, caulking and tape to ensure an air tight construction.

No combustion appliances were specified for the home. A constant room temperature is maintained on the coldest days by a ground source heat pump with a hydronic radiant heat distribution system. Efficient appliances like the kitchen’s induction cooktop and the LED lighting used throughout the home reduce the electricity budget. Energy produced by the roof mounted photovoltaic system is sold into the Ontario power grid through the province’s MicroFIT program.

Additional green design strategies such as the home’s rain-water harvesting system, the use of Forrest Stewardship Council certified lumber, the use of zero volatile organic compound paints and proximity to a diverse cluster of urban conveniences all contribute to this building’s LEED Platinum certification.

Designer: VERT plan.design.build
Images Provided by: VERT plan.design.build