How to Fix Uneven Heating and Cooling in a Two-Story Home

When you go upstairs in the summer, is it easily 10 degrees warmer than the downstairs? You try turning your thermostat down, but now your downstairs starts to freeze! If you have family living on both levels of your home, now you’ve got a battle over the thermostat, and nobody is happy. Somebody is bound to be uncomfortable.

So how do you settle this frozen downstairs or scorching hot upstairs conundrum?

Solution 1: Use a Zoned System

Most contractors would suggest getting a zoned heating/cooling system.

While our article on zoned systems describes them in more detail, we’ll give you a brief summary here.

A “zoned system” divides your home into at least two heating/cooling zones, the upstairs and downstairs (if you have a two-story home) so that you can cool and heat them at different temperatures.

There’s two parts to how this system works:

  1. Electronically controlled dampers in your ductwork – These dampers are like valves that open and close to control the flow of your heated and cooled air throughout your home.
  2. Multiple thermostats – There’s a thermostat for each zone so you can control the electronic dampers in your air ducts. So now there’s no more fighting over the thermostat setting!

The other type of zoned HVAC system involves ductless mini-split units, which are a form of ductless heating and cooling. Instead of using dampers, multiple indoor air handlers are installed throughout your home, each with its own thermostat. You can install up to 4 indoor mini-split units for each outdoor heat pump.

You may have seen these small, sleek machines inside of a hotel room. Air is discharged directly into the room, no ducts needed.

Solution 2: Find and Fix Underlying Problems

While zoned systems are effective, there may be other reasons your upstairs isn’t cooling correctly.

You should address these underlying problems first before considering a zoned system.

  • Blocked Soffit Vents – Soffit vents allow outside air to enter your attic at the lowest point of the roof. Insulation or other material may have fallen into the soffit area.
  • Blocker Supply and Return Vents – Go around your home and make sure you don’t have any drapes, furniture, rugs, or anything else blocking supply and return vents. They should all be open and unobstructed. You may think it’s a good idea to close or block the downstairs vents to cut the amount of cool air it receives, but that’s not a good idea. If you want to redirect the air to a different part of the home, ask your HVAC technician about installing dampers in your ductwork to create HVAC zones (see above).
  • Turn Fan “On” – Usually, the fan setting is set to “Auto.” This turns on the fan whenever the heating or cooling system is on, but for the rest of the time it is off. When you turn it “On,” the fan will continually circulate air throughout the home. This can help even out temperatures throughout the home. Keep in mind that running the fan will raise your electric bill, but not by much.
  • Leaking Air Ducts – If the ducts connected to your second floor are leaking cold air, then of course your upstairs will not be cold. Unfortunately, the average air duct system loses around 20-30% of its conditioned air to cracks and gaps in the ductwork. Learn how to test your air ducts for leaks. Get them sealed by a professional if that’s the case.
  • Insufficient Attic Insulation – Can you see your attic’s floor joists? You don’t have enough insulation in your attic! Learn about your attic insulation options to increase comfort and savings. Learn some DIY attic insulation tips or call a professional to get it done.

Whether you need more insulation, your ducts sealed, a zoned system or just want some advice, contact us online for help!

Service Champions is dedicated to providing the best heating, cooling and air quality services to the residents of the East Bay, South Bay, and Sacramento areas including Pleasanton, San Jose, Concord and more.

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