Challenges of Building Envelope Airtightness Testing using only a Portion of a Building

Wednesday May 8, 9:45am – 10:45am

Grand Ballroom

Currently there are standards (ASTM E-779, USACE Air Leakage Protocol) outlining the methodology and procedures to quantifying building envelope airtightness, using the building as a whole. However, there is currently no widely accepted standard that outlines the methodology and procedures that can be used to quantify building envelope airtightness using only a portion of the building (also known as sectional or sampling methods) Due to the lack of standards for this procedure and method, individual consultants / testers are having to come up with the variations of approaches, which are currently not standardized.

Sectional or sampling approaches can have inaccurate and widely misleading building envelope (BE) airtightness results due to unknown factors that are different for every building.

Most people using these approaches are not aware that there are different levels of uncontrolled or challenging conditions that are manipulating variables (different for every building) and can lead to reporting inaccurate airtightness results. Consultants/Testers can misinterpret and misrepresent the BE airtightness performance of a building. Builders can be misled of actual constructed BE airtightness performance, and be misguided that there are no deficiencies (if underestimated) or unrealistically too many issues to possibly fix (if overestimated).

There is no standard that verifies validity and repeatability of the data, where data measurements can be different every dataset, leading to high uncertainties and inaccuracies of the true building envelope airtightness.

Having collected empirical data from the testing of multiple towers, the results have the following variations, leading to invalidity and non-repeatable results.

Learning Objectives:

  1. Review and discuss metrics that help achieve validity and repeatability of building envelope airtightness results.
  2. Discuss theoretical assumptions and dynamic airflows within a building, leading to inaccuracies with sectional or sampling approaches, when attempting to measuring building envelope airtightness using only a portion of the building.
  3. Review and discuss airtightness data and results from various building / case studies
  4. Discuss research that has already been done, and discuss research left to be done before being able to standardize (if possible) a methodology, verify validity and repeatability of BE Airtightness testing using a portion of a building going forward
Level of content:
Intermediate
75%

Steven Wong

Morrison Hershfield, Burnaby BC

Stephen is proficient with new construction building envelope design/field review, building component energy modeling, and research projects driven to maximize building envelope performance. Stephen is a project manager and an industry leading specialist in practice and computations to meet building envelope airtightness standards, particularly for Passive House and BC Energy Step Code high performance buildings.