HVAC, Return Air, Garage, Firewall

I ran across something in an inspection yesterday and want to make sure I’m calling it out correctly. The HVAC unit is in the attached garage and the return air vent is in the house. Is this a hazard? Or is it safe because there’s a door?


I hope the pictures are helpful to see what I’m describing.

With the door open, I can see directly through the grille from living room to garage. The door seals well when its shut but I worry if this is a hazard.

Any input is appreciated.

What type door is that? Is it fire rated as the entry garage door is required to be?

Test the walls in the garage with your smoke pen.
Don’t have on I’m sure.
Use incense at the floor with everything closed up. If you smell it inside the house, it’s a problem. You can also see the smoke being sucked in through holes.

If it is fire-rated and completely sealed when closed is it okay?

In my opinion, the return air should be ducted back to the air handler to prevent drawing carbon monoxide and fuel vapors from the garage area. I would write it up as a safety concern and let the buyer decide if they want to address it or not.

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As long as nothing leaks through the walls. The HVAC duct penetration into the house must be metal if it is anyway connected to the garage.

I would advise your client and let them decide (testing this in not part of a HI).

I can almost guarantee that they did not spend the time and money to seal that utility room when adding a duct would be easier and cheaper. The duct would not need to be metal because it is not penetrating the fire barrier.

Because the jumper grill is so big, there would be little or no negative pressure to create a substantial leak, but I would leave the decision up to the client, Again, testing is not your job, but your observation is a credible concern. So just document your observation, no further evaluation is required. It’s up to the client. They were advised. Your SOP does not require analysis or the reason or method of repair. You can not “observe” if this thing is working.

My thought is that is should be sealed. Regardless that the door seals when closed, if that door is NOT shut you will be drawing air in from the garage. Imagine if it was not shut and the car was running in the garage…could be deadly.

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Big thanks to everyone that replied. I put it in the report. I’m still new to this and I’m so thankful to have support here.