While the use of recycled and reclaimed building materials, mechanical systems utilizing renewable energy resources, and high performance thermal envelope systems all contribute significantly to the realization and maintenance of sustainable buildings, the process of designing sustainable architecture begins with basic planning principles that embrace limiting building size, giving consideration to solar orientation/exposure and efficient building configuration. It is not until these basic planning principles have been addressed that the appropriate and disciplined selection of building components and systems can be pursued as an extension of the fundamental architectural strategy.
High Performance Building
Once environmentally informed planning principles have been addressed, the careful consideration and design of the building envelope takes precedence. Detailing for drainage, moisture and air infiltration coupled with planning for thermal isolation of the building structure informs the selection and distribution of building materials outside and inside the building. The resulting ‘tight’ building requires integrated ventilation to assure optimal indoor air quality, and the recovery of conditioned (heated/cooled/moist) exhaust air.
Indoor Air Quality
High Performance building practices result in what are referred to as ‘air-tight’ buildings. With air-sealing properly achieved, indoor air quality can only be assured with mechanical air changes. Removal of interior conditioned air and its displacement with makeup air affords the opportunity to harvest heat and reintroduce its complement, the HVAC (Heating, Ventilation and Air Conditioning) system. The small amount of power required for Heat/Energy Recovery is more than compensated for by the reduced demands on the heating/cooling equipment. Additionally, consideration must be given to the fixtures and finishes that will complete the interior of the buildings. Finishes, surfaces, fabrics and all other components that makeup the building interior must be assessed for their VOC (volatile organic compound) content. Low or No VOC products are a requirement for air-tight buildings.
Carbon Neutrality (Embodied and Sequestered Carbon)
In a culture and society that values the challenging goal of attaining Carbon Neutrality, building strategies need to address not only the Operating Costs addressed by building performance strategies, but the selection of (natural) materials that both limit utilization of carbon intensive materials but also embrace those that sequester and reduce or eliminate the embodied carbon accumulated by building material production. These selections also support Indoor Air Quality goals. The Natural Building Movement and Low Carbon Architecture are emerging and viable movements that projects need to embrace and incorporate.
Many clients approach the studio only months or weeks prior to an anticipated construction start. The response is to advocate for the appropriate amount of time for careful planning and consideration of the project. The time required is less driven by the design, drawing and specification process, than by the opportunity to provide time for the thoughtful consideration of the development of a project while it is still in design. Design/Planning time is directly proportional to the complexity of the project, with a basic 1:1 relationship of planning time to construction time. This will assure that the drawings are coordinated, and that the client has had adequate time to engage, consider, and approve the work. Revisions and changes are best accommodated before construction, and there is no substitute for planning time to manage and minimize the number of changes that could occur during the construction phase of a project.
Projects cannot be undertaken without a clear understanding of the anticipated budget parameters involved. While cost reference guides can be obtained for commercial construction, assessing residential construction costs can be more elusive. Cost per square foot projections remain the preliminary estimating tool of choice (lacking other options) while a project remains in the ‘schematic’ phase. The difficulty here lies in what actual amount to ascribe to the cost per square foot equation. On this topic there is and will continue to be disagreement, and the multipliers are refined and updated for preliminary projections on new projects, as data is obtained and analysed on finished projects. It is only when the project drawings are developed and the work can be broken down into quantifiable materials, systems and associated costs that more project specific numbers can be obtained.
Collaboration and Project Delivery
A specific project will come with a series of goals and intentions that include intention, size, required spaces and adjacencies, performance goals, cost and schedule. Addressing these successfully requires the determination of clear Guiding Principles and an awareness of the roles of all of the collaborators.
Owner: Project Goals, Decisions, Funding
Architect: Organize goals, guide decisions, understand and guide expectations for cost.
Consultant: Provide expertise in project specific areas ranging from structure to comfort.
Builder: Provide pre-construction input, determine thorough pricing projections and safely execute construction.
Approaches to assembling an effective process and team have evolved over time, and projects can be executed utilizing traditional or more progressive approaches, as summarized here:
Competitive Bids remain the traditional approach to quantifying and verifying project costs and securing a General Contractor with appropriate qualifications and agreeable pricing for the work. This approach requires preparation of detailed drawings and specifications including Architectural, Structural, Mechanical, Civil and Landscape Drawings. Complete documentation is an absolute requirement to obtain comparable proposals for a project. Such an approach requires adequate budgeting for ‘soft’ costs and appropriate timing for the back and forth that is inherent in this traditional process.
There are other approaches to assessing potential builders and quantifying cost that are worthy of consideration.
Construction Management couples ongoing consultations with a construction professional during the design phases with updated cost projections as the project and its documentation evolves. The result is an opportunity to understand cost implications as the design of the project unfolds, making the best use of time, and minimizing the potential for wasted design work, and the timing required to wait until complete drawings are available for Bid pricing. While retaining a Construction Manager may entail cost at the front end of the process, it will more than likely pay for itself with the savings in time, design revisions, and budget reconsiderations.
Integrated Project Delivery is the most progressive approach to project planning. It involves assembling a team consisting of the Owner, Architect, Engineering Subconsultants, Landscape Designers, Building Professionals, and project specific consultants at the front end of the project. With the determination of Guiding Principles and clearly articulated goals for the project, the team collaborates to identify both opportunities and liabilities as the project takes shape. The goal is to identify and address all potential issues while the project is in its most malleable form, so that designs and specifications progress in a productive and disciplined way. It is an approach that is circular at the front end, but transitions toward a linear delivery and a smooth and predictable implementation.