Why We Remove Mini Plenums

If your house was built in the 90s or later, you might have some mini-plenums in your attic. These look like boxes with holes on each of the sides, and they are used to split your air ducts three ways.

The Problem With Mini-Plenums

Replacing ductwork in a customer's home

Air moves from your AC system through your ducts. A mini-plenum is meant to split that airflow so that it goes into three different rooms. This seems like a good idea. The problem is that air moves through the path of least resistance, which is forward, straight through the mini-plenum in one direction. Air doesn’t naturally turn into the ducts on the sides of the box.

This means that most of the airflow will go into one room, while the other two don’t get much air at all. In the summer, this means you get hot people.

What We Do Once We Remove Them

We remove most of the mini-plenums we find. Instead of these boxes, we split the ducts once. We only want one run of duct to split one time—we don’t want any to split three times! One split will cover two rooms, and give us enough airflow to easily manipulate the temperature. If your thermostat says 75, we want it to be 75 everywhere. The two rooms on the sides of your mini-plenum are not going to be 75!

Your Next Step

Do you have rooms that never seem to get cool in the summer?

Call us at (972) 423-1279, and we will take a look at your air conditioning system and your ducts and find a way to make your whole house comfortable