We install a range of whole house fans sized to the home rather than a single model we push on everyone. The important variables are airflow capacity, mounting style, damper quality, and noise — and airflow is the one that determines whether the fan actually works.
Sizing Is the Whole Game
A whole house fan is rated in cubic feet per minute, and the right capacity depends on your home’s volume, not just its square footage. High ceilings change the math considerably, and Hill Country homes have plenty of those.
The general target is enough airflow to exchange the air in the house several times per hour. Undersize it and you will run it constantly for a disappointing result. Oversize it without adequate attic exhaust and you create back pressure, noise, and in the worst case a backdraft risk on combustion appliances.
We calculate what your house needs before recommending a unit. This is not a product where the biggest available option is the best one.
Mounting Styles
Traditional joist-mounted fans sit directly in the ceiling with a large grille below. They move a great deal of air for the money and are the most cost-effective option, but the fan motor is close to the living space, so they are louder, and the standard louvered damper seals poorly in winter.
Ducted or remote-mount fans place the motor away from the ceiling opening and connect through insulated ducting. They cost more and are dramatically quieter, which is what most homeowners actually care about, since the fan runs in the evening when the house is otherwise quiet.
Multi-speed and variable-speed units let you run low and quiet overnight or high for a fast flush after a hot afternoon. In practice most people use the low setting far more than they expected to.
Dampers Decide Your Winter Bill
The damper is the component that separates a good installation from an expensive mistake, and it is the one nobody asks about.
When the fan is off, that ceiling opening is a direct path between your conditioned living space and your attic. A cheap gravity louver seals poorly and leaks conditioned air all winter. Insulated, motorized damper assemblies close tightly and carry an insulation value of their own.
The additional cost is modest. The difference on a heating bill over the life of the fan is not.
Attic Exhaust Is Not Optional
This is where most whole house fan installations fail, and the fan gets blamed for it.
A whole house fan pushes an enormous volume of air into the attic, and that air has to get out. If net free vent area is inadequate, the fan cannot reach its rated airflow, it runs loud, and the attic pressurizes. We calculate required vent area as part of every quote and correct it where it falls short — sometimes with additional ventilation, sometimes alongside attic fans, which do the different job of exhausting attic heat directly.
How It Fits With Air Conditioning
A whole house fan is not a replacement for air conditioning, and we will not pretend otherwise. It is a shoulder-season and overnight tool.
Where it earns its keep in the Hill Country is spring and fall, and summer nights when temperatures drop sharply after sunset. Open the windows, run the fan, and you flush the day’s heat out of the house and the attic for a fraction of what the compressor would cost. Homeowners who use one well often leave the AC off for weeks at a stretch in April and October.
It pairs well with good insulation, which is what keeps the cool air you pulled in from being overwhelmed by heat radiating down from the attic.
Choosing and Installing
We look at your ceiling framing, attic access, existing venting, and how you actually use the house before recommending a model. Installation includes the framing, electrical, damper, sealing, and any venting corrections required to make the airflow real.
All installations are backed by our Home Comfort Guarantee, and fans get checked during seasonal AC maintenance visits.
We serve Fredericksburg, Kerrville, Boerne, Comfort, and the surrounding Hill Country. To find the right fan for your home, contact 72 Degrees or call (830) 468-5316.
