Why is My Home Always Hot Upstairs?

In the summertime in Missouri, it gets hot, and sometimes it gets boiling! 

As a seasoned heating and cooling advisor, one thing I have noticed over the years is poorly designed multi-level homes. A lot of older two-story homes in the O’ Fallon area are designed with just 1 HVAC system to condition both zones. 

This unlikely comfort design becomes a problem for a multitude of  reasons:


When your HVAC system in O’Fallon is located in the basement, and the furnace blower has to  push air from the back corner of the basement to the upstairs room that is the farthest possible location from the furnace, the airflow going that far spot is going to be less than airflow going to locations closer to the unit. 

We all know heat rises, so in order for the air conditioning system to properly cool the upper level, it must remove more heat than the lower levels. This creates an issue if you have the same amount of “cool” air going to the upstairs as the lower level. 

A good design plan can help alleviate these issues, but unfortunately, by the time the homeowner knows it’s an issue, it’s usually far past the design and build stage.


Another issue can be insulation and sun exposure. Since the home’s upper level has no livable space above it, the sun and heat from the attic will have a higher heat load on that portion of the house. 

If the attic is not insulated correctly, the air will be able to mix a lot easier and cause hot/cold spots, drafts, increased energy bills, and more. It is essential to have a properly sealed house insulated with suitable materials and an O’Fallon HVAC system designed to account for the increased heat load of the upstairs. 

Underperforming Air Conditioning System

Lastly, if your air conditioning system is just plain underperforming, your upper level will not be as comfortable as it should be. If you are experiencing this in your home, it may be time to contact an O’Fallon HVAC professional. 

Unfortunately, by the time you figure out the problem may be from a design error, it’s usually far past the planning and building stage. Still, we do have multiple solutions at Stay Cool Climate Control that can cool down your upstairs. We truly believe we can change someone’s life when they live on an upper level that is consistently 10 degrees hotter than the first floor. 

Contact us, your O’Fallon comfort advisor. We are seasoned in all things heating and cooling in the area, hence the trusted experts of your neighbors!

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