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Humidity & TemperatureWhy The Thermostat Doesn’t Tell The Whole StoryBack to HVAC 101
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TL;DR - What You'll Learn
✔ Humidity affects how warm or cool your home feels, even when the thermostat stays the same.
✔ High humidity makes it harder for your body to cool itself, making your home feel warmer.
✔ During Austin's shoulder seasons, your air conditioner may not run long enough to remove enough moisture.
✔ Humidity affects how warm or cool your home feels, even when the thermostat stays the same.
✔ High humidity makes it harder for your body to cool itself, making your home feel warmer.
✔ During Austin's shoulder seasons, your air conditioner may not run long enough to remove enough moisture.
Central Texas doesn't have just a heat problem — it has a humidity problem.
Each spring, humidity begins to rise long before the hottest days of summer arrive. In the fall, tropical systems and changing weather patterns often bring another increase in moisture. During these times of year, temperatures may feel pleasant outdoors, but indoor humidity can quietly climb.
In the HVAC industry, we call these times the shoulder seasons — those times of year when outdoor temperatures are mild but the humidity level remain heightened.
Because your air conditioner isn't running as often, it removes less moisture from the air. As a result, many homeowners notice that:
- Their home feels sticky or muggy.
- Cooling feels less effective
- The thermostat says one temperature, but the house feels much warmer.
Why Humidity Changes How Your Home Feels
Two homes can have the exact same temperature and feel completely different.
Your thermostat only measures temperature. Your body, however, responds to both temperature and humidity.
As your body warms up, it cools itself by evaporating sweat from your skin. When humidity is high, that evaporation happens more slowly, making it harder for your body to cool itself. Even though the thermostat hasn't changed, you feel warmer and less comfortable.
That's why many homeowners lower the thermostat when the real problem isn't temperature, it's excess moisture in the air.
- 74° at 50% relative humidity typically feels comfortable
- 74° at 65% relative humidity can feel several degrees warmer
Your thermostat only measures temperature. Your body, however, responds to both temperature and humidity.
As your body warms up, it cools itself by evaporating sweat from your skin. When humidity is high, that evaporation happens more slowly, making it harder for your body to cool itself. Even though the thermostat hasn't changed, you feel warmer and less comfortable.
That's why many homeowners lower the thermostat when the real problem isn't temperature, it's excess moisture in the air.
Understanding Humidity Targets
The EPA recommends maintaining indoor humidity between 30-50% relative humidity (RH) for comfort and to help limit biological growth.
However, ASHRAE Standard 55 recognizes that thermal comfort is not defined by a single humidity setpoint, but by a combination of factors and acceptable conditions over a range. You can read more about ASHRAE standards, including 55, on their standards page. In practice, ASHRAE guidance commonly places comfort within a broader band (roughly 30–60% RH), rather than a fixed value.
In Austin, a more practical target is an overall trend near ~50% RH with occasional periods in the low-to-mid 50s during particularly humid weather.
However, ASHRAE Standard 55 recognizes that thermal comfort is not defined by a single humidity setpoint, but by a combination of factors and acceptable conditions over a range. You can read more about ASHRAE standards, including 55, on their standards page. In practice, ASHRAE guidance commonly places comfort within a broader band (roughly 30–60% RH), rather than a fixed value.
In Austin, a more practical target is an overall trend near ~50% RH with occasional periods in the low-to-mid 50s during particularly humid weather.
Why Doesn’t My Air Conditioner Fix This?
Air conditioners remove both heat and moisture, but they're primarily designed to control temperature. During the shoulder seasons, your home may reach the thermostat setting quickly because outdoor temperatures are mild. Since the system doesn't run for very long, it has less opportunity to remove moisture. That's one reason humidity problems often become more noticeable in the spring and fall.
We take a closer look at how air conditioners remove moisture—and when additional humidity control may be needed—in our article on Humidity Control & Air Quality.
If your home feels cool but still uncomfortable, Bluebonnet A/C Services can help determine whether humidity—not temperature—is the real issue. Call 512-470-6240 or book online to schedule an evaluation.
We take a closer look at how air conditioners remove moisture—and when additional humidity control may be needed—in our article on Humidity Control & Air Quality.
If your home feels cool but still uncomfortable, Bluebonnet A/C Services can help determine whether humidity—not temperature—is the real issue. Call 512-470-6240 or book online to schedule an evaluation.