Tags: Marty Lapedus

17 Apr 2009, Comments Off

CFC Reviews CMHC Design Report: GUIDELINES FOR DELIVERING EFFECTIVE AIR BARRIER SYSTEMS

Author: admin

ABSTRACT

The negative impacts that can be attributed to air leakage through the building envelope are primarily threefold:

  1. damage to the building envelope components;
  2. increased heating and cooling loads resulting in excessive energy consumption and a subsequent increase in greenhouse gas emissions; and
  3. occupant health and comfort issues caused by drafts, the entry of dust and pollution into residential living quarters, and wetting of materials which can stimulate the growth of mold and mildew.

The growing North American concern in these regards is the driving force behind the development and implementation of more stringent government regulation for air barrier systems in buildings, including those buildings classified within Part 3 of the National Building Code of Canada. As it is only recently that air barrier system technologies have begun being applied on a widespread basis in North American buildings, it can be reasonably expected that flaws would exist in the current ‘process’ of air barrier system design and installation. The prevalence of premature building envelope failures, increasing levels of energy consumption, and health concerns would suggest that the quality of air barrier installation is questionable. While air barrier system failures are most commonly the result of installation deficiencies, there are instances where material and/or design flaws are factors contributing to the system failure.
This article presents a methodology to help both designers and installers deliver an air barrier system that meets the requirements and recommendations of the National Building Code of Canada and any specifications particular to that project. Common design and installation flaws will be identified, and a protocol for the inspection and testing of the system, as it is being installed, will be documented. Reviewed by Marty Lapedus.

11 Apr 2009, Comments Off

CFC Reviews CMHC Design Report: IDP — An Example of Oppor tunity for Synergies—“Tunnelling Through the Cost Barrier”

Author: admin

How do these elements come together on a project? We often hear talk about “capturing synergies” with integrated design but what do we really mean? Let’s look at a common example. Typically, high-performance glazing costs more than standard glazing that satisfies the Code requirements, and so it is rarely specified. What happens if that highperformance, solar-control glazing reduces the air-conditioning load enough that the mechanical system duct size can be reduced significantly? Now the structural beams can be reduced in depth, and floor-to-floor height can be reduced. Mechanical, structural and cladding costs have come down—perhaps enough to pay for the high-performance glazing. If the building is tall enough, perhaps an extra floor can be added while still fitting under height restrictions.

What happens if the better glazing and insulation improve wall and window thermal properties enough that perimeter radiant heating is not required to maintain cold weather comfort or the window properties are able to reduce overheating in summer?
Now you have gained back at least an extra six inches of leasable space around the building perimeter, saved energy costs and have more satisfied occupants. These measures can increase the client’s rate of return—again paying for the improvements in envelope performance.

Any one of these improvements, if looked at in isolation, would not be considered affordable. Savings like this will not be realized unless there is an integrated process where the mechanical and structural engineers, energy modeller and likely the cost consultant and property management, are all sitting down very early on with the architect and talking about building envelope and its impacts on other systems.
Without the dialogue at an early stage, no system will be supportive of any other system and the synergies won’t be captured. These are some examples of synergies, but nearly every project will reveal other opportunities. Improvements like this are more affordable if done together than if done separately. Amory Lovins of the Rocky Mountain Institute, first identified this possibility which he calls “Tunnelling Through the Cost Barrier,” Reviewed by Marty Lapedus.

5 Apr 2009, Comments Off

CFC Reviews CMHC Design Report: IDP — How is IDP Different? — Non-traditional expertise

Author: admin

Technical aspects of the design may require expertise that the core team does not possess. A daylighting modeller can quantify daylight contribution that can lead to changes in switching design. An appraiser can calculate improved development residuals resulting from green design. A site ecologist can be included for constructed wetland design.
Other non-buildings-related expertise may be helpful. For example, one successful recent green building project designed for an inner city brought in a university student working on a thesis about social interactions in the city’s core, which helped respond to the organization’s intention to have the building support local community life. Another example of new expertise helping the design team to explore alternative design issues is demonstrated by the Seville Theater Redevelopment Project: Integrated Design Process. Reviewed by Marty Lapedus.

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AIR Alexander Building Canada Canadian Funding Corp. Canadian Funding Corporation CFC cmhc construction Design IDP integrated design Moishe Alexander performance report Reviews Window Window Installation
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