Make room for density

Located in the Grandview Woodland neighbourhood of Vancouver’s east end, the original house was representative of the houses constructed during the early decades of the last century: poorly insulated, disconnected from the street, and with little natural light. The new owners – young professionals with modest funds and a new baby – looked to transform the house to suit a contemporary lifestyle with an eye to sustainable building.

BY IAN ROSS MCDONALD
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Renovation a model for improving Vancouver’s existing housing stock

STRATEGIC DECISIONS
While the project contains numerous sustainable strategies like low-VOC paints, high-efficiency fixtures, and in future may include on-site water reclamation, and solar hot water, the most important operation was the simple act of lifting the existing house to make livable the ground floor.

This radically altered the ground floor, introducing light and air, and changed the house’s relationship to the surrounding grade. It also preserved more than 60% of the existing shell of the house, saving construction costs directly and making for faster approvals with the City.

The success of the renovation could be a solution to the housing affordability problem in Vancouver – the idea of doing modest alterations in the city’s urban fabric rather than relying on grand, expensive ambitions.

For this renovation the owners maintained rigorous control of both the budget and material and product selections to make the project possible. Limited by a modest budget, but with high sustainability aspirations, the project team rarely discussed the house in terms of ever being “complete”. Here, the initial architectural operations of lifting the house and renovating the building envelope provide a base for future improvements.

COMMUNITY
The house is within walking distance of Commercial Drive, one of Vancouver’s significant cultural streets and abuts a local park. Both were important in the property’s selection as they provide easy access to commercial and cultural amenities, as well as casual recreation. The site had no pre-existing parking, and because the owners elected to maintain the majority of the existing house, they were not forced by the city to provide on-site parking.

Equally important for a house is that community also exists at the scale of the family unit. Here, significant effort was dedicated to the reconfiguration of the house so that it might provide a more communal experience than was possible in its original design.

SITE ECOLOGY + WATER CONSERVATION
Most small-scale residential projects are bound by the practical limits of their property boundaries, and this is no exception. The primary neighbourhood asset is McSpadden Park to the north, providing views and access to recreation. While this was a significant factor in the Owner’s selection of the site, the park also drains to the south, presenting a significant challenge.

The solution in future [when funds become available] is to have on-site water management and to capture water directly from the site [both rainfall and user waste], and from off-site. The advantages to managing site drainage are obvious and the owners hope that in future the water will prove a valuable resource – and not just for watering the garden.

LIGHT AND AIR + ENERGY PRESENT AND FUTURE
The introduction of natural light and air into the lower floor was the primary concern, and if there are scale advantages to small floorplates it is that every single room has access to operable windows and no where is anyone further than 20 ft. from a window.

High-efficiency fixtures are common in many projects, and so here too; however, the owners elected to establish select zones in the house to help manage energy costs and family squabbles.

A similarly contemporary attitude was taken to heating the house. Rather than installing baseboard heaters on the ground floor [frequently identified as carbon-neutral in hydro-power-rich British Columbia], the owner’s went with a radiant floor heating system.

Finally, if raising the second floor represents the primary significant operation, then the second was the complete overhaul of the existing wall assembly. Mineral fibre insulation was identified early in the process as the preferred solution and is employed in the existing and new stud walls, and outboard of that three inches [the maximum approved by the manufacturer] of mineral fibre insulation board is cantilevered, producing a wall depth that ranges from nine inches to nearly a foot.

PROJECT CREDITS

  • Architect Bruce Carscadden Architect Inc.
    Builder Alexis Morgan
    Engineer Formosa Engineering Inc.
    Photos Sham Sthankiya, Bruce Carscadden Architect Inc.

MATERIALS

  • – Original wood framing combined with engineered wood and insulated concrete forms for the new first floor; mineral fibre insulation in existing and new stud walls, and 3 in. of mineral fibre insulation board on the wall exterior, producing a wall depth that ranges from 9 to 12 in. rock-dash stucco finish and western red cedar siding.
  • – Radiant floor heating in the ground floor slab is supplied by a boiler.
  • – The windows used on this project are triple-glazed and fiberglass framed by Cascadia Windows in Langley, BC. These windows are extremely thermally efficient with overall U-values between 0.15 and 0.18 [R-value between R 5.5 and R 6.5].
  • – Bamboo flooring in selected areas and reclaimed lumber counters.

Ian Ross McDonald is a project architect with Bruce Carscadden Architect in Vancouver.