Tight house & carbon dioxide build-up (part 1)

For those of you who are counting….yes, this has become our third house with challenges. First was toxic drywall / sinkhole house. Second, was a rental house with mold. This house was built very well and very tight. Tight is not the problem, but a tight house which is not properly ventilating is a PROBLEM! Yes, three house. No, we couldn’t even begin to make this up!!!

Earlier in the year, we posted about our hvac units being oversized and unfortunately since then we have had an ongoing stress in our life of needing the units to be installed properly. If you didn’t read “HVAC 101 Crash Course: Bigger is not better” then click on the February 2020 post.

While walking through our self-taught A/C 101, we learned about tight houses and the importance of air flow. I knew something was affecting my health, as I would wake up with a specific headache in the middle of the back of my head and felt unusually sleepy. Not tired or exhausted, but SLEEPY and eyelids heavy while trying to homeschool my boys. While researching, I learned that tight houses tend to have a build-up of carbon dioxide if the air is not ventilated correctly. My online purchase of a carbon dioxide (not to be confused with carbon monoxide) meter was bittersweet, as it was good to know that my symptoms were real and had a root cause, but not so good to know that our air conditioner system was still not operating appropriately – or safely.

We had discovered that the carbon dioxide was too high in our home and the system was still problematic. Through phone calls, we found a gentleman who lived four hours away from us who said he was too far away to help us directly but would consult as a pay-it-forward favor. We were so thankful! He helped us to confirm that the fresh air damper, dehumidifier, and a/c system were not interlocked. A turning point came with his suggestion to turn on the exhaust fans in the house to see if the carbon dioxide would lower. That improved the level of carbon dioxide, but leaving exhaust fans running was not a long-term answer; it was too noisy, not how it’s supposed to be, and overall just not acceptable. 

The challenge continues for the system to be installed correctly…. and now we have come to an end with the current company and are searching for a company who can bring resolution to the situation.

You can google “tight house carbon dioxide” and read that this is a real issue. The link below is not to endorse the company, but to share simple information about a very real problem.


The carbon dioxide meter purchased, which sits on our kitchen counter…

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