Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles

TitleSealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles
Publication TypeJournal Article
Year of Publication2001
AuthorsMark P Modera, Olivier Brzozowski, François Rémi Carrié, Darryl J Dickerhoff, William W Delp, William J Fisk, Ronnen M Levinson, Duo Wang
JournalEnergy & Buildings
Volume34
705
Issue7
Pagination705-714
Date Published08/2002
Keywordsducts, leakage, SMACNA
Abstract

Electricity energy savings potential by eliminating air leakage from ducts in large commercial buildings is on the order of 10 kWh/m2 per year (1 kWh/ft2). We have tested, in two large commercial buildings, a new technology that simultaneously seals duct leaks and measures effective leakage area of ducts. The technology is based upon injecting a fog of aerosolized sealant particles into a pressurized duct system. In brief, this process involves blocking all of the intentional openings in a duct system (e.g., diffusers). Therefore, when the system is pressurized, the only place for the air carrying the aerosol particles to exit the system is through the leaks. The key to the technology is to keep the particles suspended within the airstream until they reach the leaks, and then to have them leave the airstream and deposit on the leak sites. The principal finding from this field study was that the aerosol technology is capable of sealing the leaks in a large commercial building duct system within a reasonable time frame. In the first building, 66% of the leakage area was sealed within 2.5 hours of injection, and in the second building 86% of the leakage area was sealed within 5 hours. We also found that the aerosol could be blown through the VAV boxes in the second building without impacting their calibrations or performance. Some remaining questions are (1) how to achieve sealing rates comparable to those experienced in smaller residential systems; and (2) what tightness level these ducts systems can be brought to by means of aerosol sealing.

DOI10.1016/S0378-7788(01)00120-7
LBNL Report Number

LBNL-42414