The Undercut and Airflow in Your Home

It’s the holidays and the kids are out of school. That means now is the time to talk about the air flow in your home.

 All mothers know exactly how what will fit beneath the bathroom undercut.

All mothers know exactly how what will fit beneath the bathroom undercut.

“Wait. Did I hear that correctly? Did you say airflow?”

Yes, you did. In fact, now is the perfect time to talk about the airflow in your home, particularly if you have a teenager or budding teenager, who has strategically locked themselves in their room.

Well, that closed door has a small crack underneath it, doesn’t it? Let’s digress on that crack for a moment. 

 Did the kid teach the cat, or was it the other way around?

Did the kid teach the cat, or was it the other way around?

The crack is known as the door undercut. The door undercut has long been a tool for small children to make a social connection with their mothers, in particular,  mothers who are in the bathroom. Whether it’s tiny, wriggling fingers, toys or other small objects shoved beneath the door, or, with the small head bent in order to be heard, their lips to the crack to murmur a tentative, “Mommy? What are you doing in there?”

What does the door undercut have to do with an HVAC?

Consider the cycle of air in your home for a moment. Starting at the filter, the air makes its way through the air return grill and filter, where it is warmed by the furnace and blown through the ducts and registers. Some of that air flows into your teen’s room and basically stops, because the supplied air flow hits the closed door, essentially cutting off the return air flow. The only way for the air to escape is from the door undercut, and if there is carpeting in the teen’s room, it may be inhibiting the circulation by slowing the returning air.

 A door grille might be the answer to poor airflow.

A door grille might be the answer to poor airflow.

Good air flow involves uninhibited air circulation. A closed door isn’t conducive to uninhibited air flow, which can create pockets of uneven temperature in the home. Poor air circulation can create a stagnant air odor and promote poor air quality in your home. Since people need fresh air to maintain health, poor air circulation can promote allergies and respiratory issues.

While we aren’t telling you to pry your kid’s door open, it will help you understand if your HVAC suddenly isn’t performing optimally.  It’s correctable with a wall grille or door grille. They come in a huge range of sizes, styles, colors and materials. Placement of a wall or door grille in rooms where the size of the door undercut is inadequate can improve air flow remarkably.

 Here is an example of a wall grille.

Here is an example of a wall grille.

If you have concerns about the circulation in your home, an HVAC expert can help diagnose and correct air flow issues.


Call us if you have airflow concerns, or if you need refrigeration or heating service in your Phoenix-area home! All-Temp Refrigeration and Heating - 480-376-7548

Green Thumb Local

Green Thumb Local LLC, 221 East Indianola Avenue, Phoenix, AZ, 85012