How To Beat The '20-Degree' Rule In Texas

Living in Texas is a constant battle against the elements. It gets way too hot here in the Lone Star State.

We are about to hit a long stretch of 100-degree days. Those wild high temperatures can leave you searching for a way to get cool.

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What Is The '20-Degree' Rule?

If your house isn't staying cool, and you call an AC repairman, he might turn the situation back on you and tell you about the 20-degree rule. When your AC system is working at its best, it can only lower the return air by 20 degrees.

According to that rule, if it is 100 degrees outside, you should only expect the house to be 80 degrees inside. That doesn't take into account that the air it's cooling is recirculated inside, not coming from outside, so it's just a rule of thumb.

Humidity also plays a big role in this equation. If the humidity is 80% like today on South Padre Island, your AC could also struggle. HVAC experts say your indoor humidity should be under 60% to be comfortable according to aircomfort.com.

AC units not only cool the air, they also work to lower the humidity. If your windows are fogging up, you know the humidity inside is too high.

How To Beat The '20-Degree' Rule

If your AC is running all day, and your home is still only 78 degrees inside on a hot day, you might think that is as good as it can get. The one real way to beat those numbers is buying a home with spray foam insulation.

Newer homes can be up to 20% more efficient.