I think that creating a solid air barrier between the laundry room andyour living space is a great idea.
However, it is going to be verydifficult to know this was achieved without a little professionalassistance. I'd recommend finding a BPI Accredited Contractor or BPIBuilding Analyst (www.bpi.org) near your home and hiring them to performan inspection.
- They should do analytical testing with a blower door todetermine how leaky your house is and if there is a solid/continuous airbarrier between your home and the laundry room.
- In addition, theyshould have some fancy indoor air quality (IAQ) testing equipment todetermine if any CO, VOCs, gas, or other unfriendly substances areentering your home.
If the basic work you performed has not solved the issue, then it wouldbe wise to have a BPI professional take it from here. Air sealing canbe complex, technical, dirty, and dangerous work.