Invisible Improvement: Air Tightening an Office in a Historic Timber Pier

Wednesday May 8, 8:30am – 9:30am

Grand Ballroom

Historic structures provide a significant cultural value and in the case of the Seattle waterfront, link the maritime period around Seattle’s founding to the current tourist and commercial center of the city. In addition to contributing to the local heritage and historic fabric, existing buildings generally also contribute disproportionately to the energy consumption of our building stock. Pier 56 was constructed in 1900 over Elliott Bay as a timber structure and for much of its history was a base for nautical transportation. Today, the lower floor of the building houses several retail and restaurant tenants. The upper floor, approximately 30,000 square feet, is leased by the architecture firm Mithun, winner of the 2023 AIA Architecture Firm Award.

Mithun leased the space in 2000 and as part of a lease renewal in 2020, completed tenant improvements including air sealing. The goal of the air tightening measures was to reduce energy use and improve occupant comfort, which was a challenge for a vaulted exposed timber structure with no cooling and no perimeter heat distribution.

This session is a case study covering the pre-improvement multi-fan air barrier testing, diagnostics completed during testing to determine leak locations, remedial work completed during construction, and the final air barrier test. We will also include pre- and post-occupancy energy use comparison and occupant descriptions of comfort improvements.

Learning Objectives:

  1. Participants will be able to identify at least three locations of air leakage in a historic timber framed structure.
  2. Participants will be able to establish a methodology for determining, designing, and confirming air tightening measures in existing buildings.
  3. Participants will be able to evaluate the value of different air sealing measures on occupant comfort.
  4. Participants will be able to understand the methods used to validate performance improvements associated with air sealing old buildings.
Level of content:

Jeff Speert, AIA, LEED AP

4EA Building Science, Seattle WA

Jeff is a Principal and Office Director at 4EA Building Science. His passion for building sustainability and durability and fascination with tectonics and construction methods led him to a building science career.

Jeff is a building science generalist with an interest in elements that provide energy efficiency, including air barriers and thermal bridging. His technical depth in building science and foundation in architecture and design has helped build the 4EA culture—tackling the challenging task of harmonizing aesthetic vision with the high-performance demands of contemporary building enclosures.

He initiated the firm’s large building air barrier testing in 2010 and has presented at regional and national conferences on building science and air barrier related topics. He is also an author of several papers on moisture protection of mass timber structures. He is a licensed architect in multiple jurisdictions.