Revised:
June 20th, 2022
Is your upstairs too hot? Is there a drastic difference between floors? Are you having trouble sleeping? You’re probably suffering from uneven temperatures, and in this video, we’ll go over the causes and how to fix it.
Hi, I’m Luke from Fire & Ice. Uneven temperatures are one of many comfort concerns many customers have expressed. If you live in a two-story home, you’ve likely experienced it. The lower level will be comfortable in the summer, but the upper level is hot and muggy. And in the winter, it’s the opposite. This has to do with how thermodynamics work and how heat rises and cool air falls. In this video, we’ll go over the reasons that can cause uneven temperatures and seven ways to fix them. By the end of this video, we hope you’ll have a better idea of how to solve uneven temperatures and be on the path to better indoor comfort.
What can cause uneven temperatures inside a home?
There are several reasons that can cause uneven temperatures in a home. The first one that comes to mind is that your system is underpowered. If your system is only capable of conditioning, say, a 2,000-square-foot home, but your house is 3,000. You’re going to run into issues with uneven temperatures.
Conversely, an overpowered system can lead to uneven temperatures too. In HVAC, bigger isn’t always better. As a result, an overpowered system can do more harm than good. HVAC is all about air distribution and mixing the air. Think of a jar of salad dressing. Shaking the jar for a few seconds won’t mix all the ingredients, and shake it for longer. When you have an overpowered system, the same thing happens. It kicks on for a short period and then shuts off again. We call this short cycling, and it can lead to uneven temperatures.
Another reason for uneven temperatures is not enough air return drops. Remember, it’s all about mixing the air and changing it over. The return air drops are responsible for taking the unconditioned air from the house to the equipment to be conditioned. If there aren’t enough return drops in the home, you’ll likely have uneven temperatures. I’ve been in homes where there’s a single return for the entire upstairs.
The fourth reason has to do with insulation and your attic’s construction. A typical attic can get well above 150 degrees during the summer if there isn’t enough insulation between the upstairs. The excess attic heat will make the upstairs warmer than the rest of the house. And in the winter, if your attic has leaks or not enough insulation, all that warm air you’re pushing to the upstairs will likely go right through to your attic. Remember, heat rises.
The last contributing factor to uneven temperatures is proximity to the garage. Having a room or space above a garage has an increased chance of experiencing erratic temperatures. Why? The air isn’t just exfiltrating out the walls and ceiling but also the floor. This is why master bedrooms or dens above a garage are notorious for dealing with uneven temperatures.
7 Ways to Combat Uneven Temperatures?
Now that we can recognize the problem let’s go over seven ways to solve uneven temperatures. Let’s start with the easy stuff. The first thing to do is to check your dampers. Dampers are located in your ductwork and are used to help direct airflow throughout your home. The easiest way to do this is to have someone adjust the damper while another person is at the vent in question to see if it increases airflow to the room. Sometimes the most straightforward solution will solve issues to a significant problem.
The second solution is to change your ductwork by adding a return air drop to the second floor. This step can be invasive since it requires removing drywall and ceiling floor panels to run the ductwork to appropriate areas, but it can be less expensive than investing in a new system. However, there are some instances where further ductwork modifications are needed, like widening the main trunk lines.
The third is investing in a variable-speed HVAC system. Variable-speed furnaces and air conditioners can ramp up and down depending on the temperature outside. It’s a lot like cruise control in your car. For example, let’s imagine a summer day, and we want to keep the temperature inside at 70 degrees. In the morning, the outdoor temperature is 68 degrees, and the need for cooling may not be as high as when it's 95 degrees outside at 3 p.m. With a variable speed system, the equipment will use 20-30% of its capacity in the morning and ramp up as it gets hotter outside. By working in lockstep with the outdoor temperatures, you’ll have more changeovers of the air inside your home, resulting in a better mix of conditioned air. For comparison, in a single-stage, on/off system, there are only 3 to 4 cycles per hour.
The following solutions are ductless-mini splits, standalone HVAC systems for a single room. Installing one in each bedroom or an area that a conventional HVAC system can’t reach will eliminate uneven temperatures in your home. In addition, each room with a mini-split will have independent control over its indoor comfort.
The following two solutions, zoning and sensors, are linked. Zoning a home uses separate HVAC systems to heat and cool different parts of the house. For example, there’d be one system dedicated to conditioning the downstairs and the other responsible for the upstairs in some applications. Zones can be created either with conventional HVAC systems, mini-splits, or a combination. Additionally, temperature sensors can be added to the mix to help the systems communicate with each other. Traditional thermostats are usually in one area and can only measure the indoor temperature in its area. Adding additional sensors inside the home can help your HVAC system know if the demand for heating and cooling is needed in other areas of the house. And if you add automatic dampers, parts of the ductwork can be opened and closed, further creating zones.
The final solution of note is budget options. Now, they may not solve the issue entirely, they can help. For starters, fans do help by circulating the air in the room. Window air conditioners and space heaters also help but won’t achieve the same comfort level as a ductless mini-split can. But if you’re truly on a budget, it’s good to know there are options that can help relieve your discomfort.
What are the next steps?
I hope by now you have a better understanding of how to solve uneven temperatures in your home. If you feel one of the solutions we just discussed is right for you, click the free estimate at the top of the screen. We’d be happy to sit down with you and discuss your options. Thank you for watching, and we look forward to making your day better.
