If your house feels hot, humid, or uneven in the Austin heat, do not assume you need a bigger AC. Start with simple fixes first: use a MERV 8 air filter, switch hot lights to LEDs, install solar screens on sunny windows, fix door weatherstripping, keep the AC fan set to auto, and use ceiling fans only when you are in the room.
If those things do not solve it, the problem is usually in the attic. In Austin homes, comfort problems are commonly caused by bad duct design, duct leakage, low attic insulation, air infiltration, or solar gain through windows.
Your AC Makes Cold Air. The House Has to Use It Correctly.
A lot of homeowners call me and say, “Jason, my system runs all day. I think I need a bigger one.”
That is almost always the wrong answer.
The AC makes the cold air, but the duct system has to deliver that air to the rooms. If the ducts are poorly designed, leaking into the attic, or restricted by a bad filter or undersized return, the rooms will not get the airflow they need.
Attic insulation is the buffer between your living space and the hot attic. When an attic only has a few inches of insulation, the house is fighting attic heat all day. That is why the system runs nonstop and still does not feel comfortable.
Low-Cost Comfort Fixes to Try First
Before spending thousands, start with the inexpensive things that actually make sense.
Use a MERV 8 Filter or Lower
Filters should usually not be above MERV 8 unless the system was designed for it. Restrictive filters reduce airflow, and poor airflow creates comfort problems.
Change Incandescent Bulbs to LEDs
Old bulbs add heat inside the home. LEDs are cheap now, and they reduce the heat load your AC has to fight.
Add Solar Screens to Hot Windows
If a window gets more than one hour of direct sunlight per day, solar screens can help. They are usually a much better comfort investment than replacing windows.
Use Ceiling Fans Correctly
Ceiling fans cool people, not rooms. Use them when you are in the room and turn them off when you leave.
Replace Bad Supply Grilles
Changing restrictive supply register grilles to one-way curved blade grilles can improve airflow. I measured about 15% better airflow in my own house with a flow hood by changing nothing but the grille.
Do Not Overspend on the Wrong Upgrade
Even though window, roof, siding, and system upgrades are common home improvement projects, the best upgrade is still the one that solves the actual comfort problem.
A bigger AC does not fix bad ductwork. Solar panels do not reduce how much heat your house gains. Smart thermostats only help if they are programmed and used on a schedule.
Replacing windows is usually not the first move for comfort in Austin heat; if the problem is direct sun, solar screens often address that issue for a lot less money.
I do not recommend spray foam as a retrofit in most existing Austin homes unless combustion safety, humidity, and ventilation are properly addressed.
The right upgrade depends on what is actually causing the comfort problem.
A South Austin Example
Phil in South Austin thought he needed a bigger AC. Someone had also recommended replacing his old windows because they got a lot of direct sunlight.
But the AC was not the problem.
His ductwork was badly designed and leaking cold air into the attic. He also had very little insulation. We corrected the duct system, sealed the leaks, improved the insulation, and fixed the real problem.
Now his 10+ year old AC runs like it should. It does not run all day, his bills dropped substantially, and the rooms are even temperatures.
When to Call a Home Performance Professional
If the simple fixes do not work and your home is still hot, humid, or uneven, stop guessing.
Do not call an AC-only contractor, insulation-only company, or window company and expect a whole-home diagnosis. They are going to sell what they sell.
A home performance contractor looks at how the house works as a system: ductwork, airflow, insulation, air leakage, solar gain, humidity, and equipment. That is the difference.
If your Austin home is uncomfortable even though the AC is running, a home performance in Austin evaluation can help identify the real cause before you spend money on the wrong fix.
The Main Takeaway
Try the simple and inexpensive things first. If the problem continues, call the right type of company before replacing windows, adding spray foam, installing solar, or buying a bigger AC.
In Austin heat, comfort usually comes from fixing the house, not just replacing the air conditioner.
