A HOUSE UNDIVIDED, TORONTO, CANADA

A simple dwelling between an expressway and the lake, A House Undivided is a two-storey wrapping wall that sits on the edges of a geo-slab. It creates four zones of use around a central stair on two levels; four plain earthy spaces that are to be occupied but hardly decorated--coded and furnished. Finding expression for modesty in spatial quality and tectonic presence has been both a conceptual framework for the project as well as a guideline for building method. How to find direct reciprocity between conceptual ideals and methods of construction? And how to re-invent the notion of dwelling in this cold climate with a new affordable and sustainable paradigm?

Building Method and Technology

Early on, during the design process. the visionary clients brought together the knowledge and experience of a green builder, an envelope and product engineer as well as the craftsmanship of a traditional lime plaster specialist to form an interdisciplinary pool of ideas and expertise to formulate the building construction methodology and thermal and tectonic concept that would be the direct expressions of the design concept in built form.

Thermal Mass - The core idea of the project’s thermal performance is to rely on thermal mass as the key component in thermal comfort of the building, a missing element in most of the common energy modeling methods while heavily present in the history of architecture. The Concrete insulated modular forms have the insulation on the outside of the concrete layer and uses concrete’s thermal mass to reduce the speed of dissipation of energy from the inside out during the cold hours and gradually store energy during the warm hours of the operation.

Breathable Walls & Hydraulic Lime Plaster - The second important shift in the design of the envelope performance is the removal of the vapor barrier layer and creating breathable walls that will not rot in the presence of moisture over time. This innovation, similar to traditional masonry walls, can breathe out the accumulated vapor pressure from the inside out.

The lime plaster and the cork coating both on the inside and outside acts as the air barrier vapor permeable membranes on both sides of the wall. Once again a historic material and application that has proved its resilience and has been virtually lost in contemporary envelope design.

Shallow Frost Protected Foundation System - This foundation method, used mostly in Scandinavian countries allowed to build over the earth as opposed to inside and is engineered to incorporate the heating equipment of the house inside its crust and through the use of a thick bed of expanded polystyrene the frost action of the earth during the winter will not uplift the building. Through the use of this method that land on the property (except the topsoil) remained virtually intact. The exposed concrete of the ground floor is the finished surface of the geo-slab.

White Roof & Exposed Light Wood Frame Structure

An inverted roof assembly allowed eliminating the presence of any kind of synthetic insulation from the indoor environment as well as allowing the expression of the roof structure inside the house. White washed river stone will act as the ballast for the extruded polystyrene insulation panels over the roof as well as creating a white roof to minimize heat island effect.

Fiberglass Windows High performance triple glazed fiberglass windows form the apertures of the house (U Value 0.22 U.S/I-P).