What kind of experience have folks had using blower doors in multifamily buildings?

I hear conflicting info on when and how BDs can be used and useful here.  What are your experiences?  Photos?

Views: 330

Reply to This

Replies to This Discussion

I did a couple of duplex/triplex units last week and was told to test one unit at a time and disregard adjacent units. I wonder if the numbers might be slightly lower if the units were all depressurized at the same time, and I may get a chance to find out.

 

More on this topic: http://www.greenbuildingadvisor.com/blogs/dept/green-communities/bl...

Blower door testing multifamily buildings is just as useful as testing single family homes. The energy savings is usually correspondingly less, since there's typically less exterior exposure. The big difference, of course, is in learning how to deal with leakage to adjacent units. In a row, or townhouse complex, this can be a very minor consideration. Adjacent units would tend, on average, to be pressurized similarly with respect to the outdoors. For accurate testing, we would want to have access to the neighbors units, either to install a blower door in them, and equalize the pressure across any shared walls, or at the very least to open a window/door to treat neighboring units as the outdoors.

 

In larger, multi-floor, buildings, the leakage within the building begins to have a significant impact. If we restrict ourselves to energy savings, and ignore the equally significant indoor air quality concerns, air leakage to the outdoors is no longer the only concern. Depending on a units location within the building, top floor vs. bottom floor etc.., the air leakage due to the stack effect (movement of warm air up the building column) can have major energy savings implications. In a cold climate, it's entirely possible to see units at the top of a tall multifamily building with their windows open. This is typically because the movement of warm air from the lower floors is so significant that the top units are feeling too hot. The net effect of opening windows, naturally, is to draw yet more warm air up, further cooling lower units, causing them to want even more heat. You can see where this is going...

 

The solution, when it comes to air sealing, is to not only isolate leakage to the outdoors, which can be done by neutralizing leakage to adjacent units and floors, but also to learn to isolate leakage to each adjacent unit, hallway, and floor. Not easy once a building becomes occupied.

RSS

Forum Discussions

How would you insulate this roof?

Started by David Butler in General Forum. Last reply by David Butler yesterday. 2 Replies

Dirty solar panels

Started by Evan Mills in General Forum. Last reply by Stacie Bagnasco yesterday. 1 Reply

Fixing a water heater?

Started by John Shillito in Best Practices. Last reply by Eric Kjelshus on Friday. 21 Replies

Latest Activity

Profile IconAvery T. Phillips, Sarah Burger, Troy Spindler and 2 more joined Home Energy Pros Forum
3 hours ago
David Butler replied to Brad Cook's discussion Too many Heat Pump Water Heaters in a basement?
"theoretically, let's say you perfectly isolate the HPWH from a heat source. The HPWH's…"
yesterday
David Butler replied to David Butler's discussion How would you insulate this roof?
"Interesting idea. Commercial roof on a slope! Typical density for roofing spray foam is 2.5 to 3.0…"
yesterday
Profile IconRandy Kinnison, Breanna Detwiler, Jeff Farlow and 7 more joined Home Energy Pros Forum
yesterday
Summer Redman added a discussion to the group Job Board
Thumbnail

Hiring 2 Training Specialists in Champaign-Urbana, Illinois

The Applied Research Institute (ARI) at the University of Illinois at Urbana-Champaign is seeking…See More
yesterday
Summer Redman joined Diane Chojnowski's group
Thumbnail

Job Board

This group is for posting jobs related to all aspects of the home performance industry including…See More
yesterday
Stacie Bagnasco replied to Evan Mills's discussion Dirty solar panels
"This is a great idea. I clicked on your discussion because it made me remember that I forgot to get…"
yesterday
Kirsten Richnavsky posted an event
Thumbnail

rCloud - The Future of Testing at Your Office or Home

October 18, 2017 from 2pm to 3pm
Integrating rCloud as an essential part of your RESNET QA process.Retrotec’s rCloud app is here,…See More
yesterday

Photos

Loading…
  • Add Photos
  • View All

© 2017   Created by Home Performance Coalition (HPC)   Powered by

Badges  |  Report an Issue  |  Terms of Service