Thursday, June 2, 2016

Blower Door / Window Door Tests

Passive House Airtightness Achieved!

We ran a few different tests today to validate our airtightness numbers:

Our Field Measured Volume is 29356 CUFT

We did a Window Blower Door Test with the Duct Blaster

Here are photo's from our "Depressurization Test"

52 CFM50 - 0.106 ACH50

Here are photo's from our "Pressurization Test"

65 CFM50 - 0.133 ACH50

We also ordered the "D Ring" for the blower door to get an accurate Blower Door Number 
I should note - the tolerance for the D-Ring is:
125 CFM - 30 CFM

Here are photo's from our "Depressurization Test"
49 CFM50 - 0.100 ACH50

Here are photo's from our "Pressurization Test"

52 CFM50 - 0.106 ACH50

To average the results we are at 50.5 CFM50 

A few notes from the tests:

  • The blower door pressurization test was done in the protected breezeway door vs the duct blaster pressurization test that was done on the open back yard. 
  • We did a blower door pressure test up to 90 Pascals to see when/if the Studor Vents (AAV's) opening would effect our results - there was no noticeable difference:
  • The Blower Door Frame was extended fully to accommodate the width of our door. The seal was probably not perfect
  • All of our plumbing is not installed yet - we will do another test once it is.
  • We were having trouble syncing our computer to the manometer to complete a multi-point test, once we do that we will post those results!
From what I could find the tightest house in the world is in Alaska - 0.05 ACH50 - we are 25 CFM50 away from that.

Stay Tuned!


  1. could you tell me what criteria you use to determine your interior volume? or direct me to a web site that details the passive house standard on what is included and what isn't? Thanks so much. Keep up the great work.

  2. 475 did a great article on their blog on how to do this:

    The standard is EN 13829, so an internet search should lead you in the right direction

  3. I have new ideas about window n door style and installation.
    window replacement