Kinark Sustainable Living Centre

Roof

A roof must serve to protect a building against the worst of the weather and handle significant structural loads while providing a dominant aesthetic for the entire building. How do we make a good hat for a building?

Design Intent

1. To protect the building from the elements: sun, wind, rain and snow
2. To use materials with the least possible environmental impact
3. To provide excellent thermal insulation
4. To provide a surface for collecting rain water
5. To create shaded and protected areas around the building
6. To collect heat for storage below the building

Materials and Methods

There are two distinct roofing systems used on this building. On the south side, conventional lumber is used to frame the roof. Strapping carries the steel roofing, and insulated panels (cutouts from a door-making factory) are attached from below to provide insulation. The steel roofing is a dark colour, and has below it the heat collection pipes for the AGS heating system (see heating section).

The north roof is framed using round Hemlock timbers, which were harvested locally and sustainably at Haliburton Forest. Attached to the LVL beams every 1.2m (4 feet), these rafters support two layers of rough sawn Hemlock planks (visible inside as the ceiling), a vapour barrier, two layers of insulation (door panel cutouts), strapping and the locally harvested, white cedar shingles. The unevenness of the timbers, as seen from inside the building, lends the roof its wavy shape.

Questions

Why use round wood for the rafters?

The logs were donated to the project by Haliburton Forest, and we wanted to make use of such a generous gift of useful, environmentally-friendly material. While they required significantly more labour to prepare and install, their low ecological impact and the visual effect of the wavy roof were positive trade-offs.

Why white cedar for the shingles instead of red?

The red cedar used for most shingles is harvested on the west coast, and often not sustainably. The amount of energy required to ship such shingles across the country is high. The white cedar version is grown and harvested locally, and is well-adapted to our colder, drier climate.

Why expose the rafters and the decking inside the building?

This building is intended to “show off” its structure, and we wanted people to see and understand the roofing system from inside the building. As exposed finishes, the round logs and the rough sawn planks continue the theme of “rough elegance” that defines many of the finishing choices.