Solved: Upstairs Is Hotter or Colder Than Downstairs

Every floor in your home should be a refuge that’s warm and toasty in the cold months and cool and comfortable in the summer. However, families who live in some multi-level residences find the upper floor is stubbornly hotter or colder than the rooms on ground level.

This could merely be because most thermostats in a house are on the main floor, which is where people spend the most time—in the living room, kitchen, etc.—so it makes sense to set the temperature according to how it feels on the first floor.

However, temperature discrepancies between the upstairs and downstairs could also be caused by issues with your HVAC system. Some of these issues can be sorted out fairly quickly while others might necessitate more extensive and costly fixes. Here, the professionals at Kelly Heating & Air Conditioning will help you figure out why the upstairs of your home is hotter than downstairs, or vice versa.

Why Is It Hot Upstairs?

The phenomenon of the upstairs of a two-story home becoming hotter than the downstairs can be chalked up to several factors. For starters, heat rises, so it’s common for the second floor of a home to get hotter than the ground floor. Lack of insulation in the attic or roof can exacerbate this issue by permitting heat transfer from the roof into the upstairs rooms.

Another common reason is that the air conditioner is not big enough to cool the entire home, causing it to struggle to cool the upstairs effectively.

To address these issues, homeowners could install extra insulation in the attic and make sure their home has adequate ventilation. If there’s concern the air conditioner is the ideal size for the home, call an experienced HVAC company like Kelly Heating & Air Conditioning inspect the unit. A knowledgeable professional also can help locate a unit that's better suited for your home if you want air conditioning installation or replacement.

Why Is My Upstairs Colder/Not Heating?

When the downstairs of your home is warm, but it’s very cold upstairs, that makes for an ice-cold night for anyone whose bedrooms are on the upper floor. The most frequent explanations for an upstairs not heating like it is supposed to are the insulation levels and the ductwork.

Inadequate insulation permits cold air to filter through the home’s attic or walls and contribute to heat loss, resulting in colder temperatures on higher floors. It’s important to make sure your home has a thick, level layer of insulation in the attic and proper insulation in the walls to keep the cold out and the heat inside.

The ductwork in a home plays a very important role in circulating conditioned air throughout different areas of the building. However, issues with the ductwork can cause the upstairs being colder than the main level. A typical reason for this is improper airflow balance. The ducts may not be the proper size or configuration, which results in an uneven distribution of air between the floors. This can cause more warm air to go downstairs, causing insufficient airflow—which is the heated air—on the upper story.

Another possible issue with the ductwork is the placement of the supply and return vents. If there are fewer vents on the upper floor or they aren't well positioned, it can restrict air circulation and cause inadequate heating or cooling. Additionally, leaks or gaps in the ductwork can allow air loss, decreasing the overall efficiency of the HVAC system and exacerbating the temperature difference.

To find out why the upstairs is colder than the downstairs, homeowners should hve their ductwork examined by trusted experts like the team at Kelly Heating & Air Conditioning to identify any imbalances, leaks or inadequacies. Sealing leaks and adding additional vents or adjusting existing ones can help enhance airflow and ensure a more consistent temperature balance between the upstairs and downstairs.

Fixing the Hot or Cold Upstairs Problem?

If your upstairs is hotter or colder than the lower floors of your home, an HVAC zoning system could be a useful solution.

An HVAC zoning system breaks the residence into distinctive zones, which each have their own thermostat and damper system so the homeowner can customize the heating or cooling of each zone.

This system can be particularly beneficial in instances where the upstairs of a multi-story home is very hot or really cold while the main floor is comfortable. By investing in a  zoning system, homeowners can manage the temperature independently in each zone, allowing them to address specific hot or cold spots effectively.

To learn more about an HVAC zoning system in Iowa City, call Kelly Heating & Air Conditioning. We’ve created and installed customized home comfort plans for many community members and are happy to show how an HVAC zoning system could work in your home.

Why Is it So Humid Upstairs?

In addition to the upper story being hotter or colder than the rest of the house, another problem in multi-floor homes is when the upper floors are more humid than downstairs.

A common reason for excess upper floor humidity is inadequate ventilation on the upper floor, which can cause greater humidity levels. As is often the case with temperature differences between floors, inadequate insulation or sealing in the attic or walls may permit warm, humid air from outside infiltrate the upstairs rooms. And, if there are any leaks or plumbing concerns on the upper floor, that can also create extra moisture in that area of a home.

To fix humidity problems, homeowners can improve ventilation by using fans or opening windows to promote airflow. Proper insulation  in the attic and better sealing the attic and walls can help prevent external moisture from entering the upstairs. Finding and repairing any leaks or plumbing issues is also extremely important.

Depending on the levels of moisture found in the home, a whole-home dehumidifier could be another helpful tool to manage humidity in your home.