Precedent vs. Innovation

Precedent vs. Innovation
Introduction / Assesment / Learning from the Past / New Solutions / Outcomes

Introduction: The Conundrum
More buildings exist today than ever before in the history of mankind. Countless variations on typical enclosure strategies are available for precedent studies that are soundly based on demonstrated performance. For many conventional buildings, designers should seriously consider the rhetorical question, "Why be original when you can be good?" New methods and materials can easily achieve excellent performance by intelligently manipulating successful precedents.

The physics governing the surface tension of water is often what keeps water spiders and architects from drowning.

Disasters are often the only way to learn about how to design and build better performing enclosures.

Assesment
Indeed a reliable approach to design involves the use of past precedent as a departure point. This is because the building enclosures of most buildings share common strategies, and it is usually possible to locate a well-performing past precedent, and perform a visual inspection. When dealing with an existing building, some analysis or testing of the envelope materials and assemblies may be necessary to quantify hygrothermal behaviour (more on this in the July 2002 Architectural Science Forum). This information may be used to assess the adequacy of an existing envelope or its potential for improvement (or preservation), in the case of retrofit projects. For new building projects, visual inspection and analysis of successful past precedents provide a yardstick to the designer. Modified envelope assemblies contemplated during design may be compared with an existing envelope to predict whether their performance is equivalent or significantly different.

Unsuccessful past precedents are also very useful, in that they instruct the designer how not to design. This is particularly important in the detailing of envelope systems, where stylistic elements may require special attention. Defects and failures represent the "dead-ends" of envelope design, and provide important navigational aids in support of viable strategies and solutions.

Water shedding patterns are made evident by the staining of the stone enclosure by the copper roofing. Massive storage capacity in the walls has enabled the enclosure to withstand the concentrated wetting.

ETFE foil cushions - new materials, old enclosure strategies.

Cast iron facades represent face seal enclosures that rely on drainage and storage and drying as secondary moisture management strategies.

Learning from the Past
As was noted earlier, the evolution of enclosure design strategies is analogous to biological evolution. The fittest survivors become design precedents upon which future generations base their work. Every city represents a full scale architectural science experiment that could not be easily duplicated in any research laboratory. Unfortunately, recent generations have not taken much interest in observing past precedents as may be gathered from the intermittent publication of best practice guides which often respond to a wave of problems associated with certain types of enclosures. Perhaps even architectural history is doomed to repeat itself.

Modern rammed earth wall rendered as an organic mural.

Rammed earth enveloped by sloped glazing depicts the delight of the mass and glass approach to passive solar heating.

Rammed earth integrated into a modern building form.

St. Thomas Church, Shanty Bay, Ontario, 1842. One of the oldest remaining buildings constructed of rammed earth in Ontario

Generous roof overhangs and conveyance of water away from the building play a major role in the longevity of St. Thomas' rammed earth enclosure.

New Solutions, Old Problems
But not all buildings are traditional or conventional, and many aspire to a level of innovation that seriously challenges architecture and its allied disciplines. New materials and methods entice clients and architects to transcend precedents in order to discover new dimensions in design. This is the conceptual moment when feasible enclosure strategies are most critical.

Contemporary application of a ziegelfassade system.

Ziegelfassade integrated with double-skin façade.

Ziegelfassades (clay tile façades) is an innovative, engineered rain screen cladding system.

Section through ziegelfassade system.

Outcomes
The challenge for architectural science is to evolve appropriate enclosure strategies that harness the potential of innovative materials and methods to fulfill their promise to contemporary architectural aspirations. This will require architects to embrace new sophisticated enclosure design tools without giving up their perspectives on the legacy of the numerous and diverse past precedents surrounding them. The Related Resources section which follows, attempts to provide some helpful information in support of these emerging opportunities.

Graduated mediation achieved through selective layers, some of which are kinetic and respond to the physical phenomena which influence them.