A word about the data before the numbers
Both of our sources on this topic are old. Fixr's guide was last updated in August 2022 and Bob Vila's in December 2023. Everywhere else in this section we can put a 2026 guide next to an older one; here we cannot, because no third publisher we can reach has a current attic fan cost guide.
We are publishing anyway, with the dates in front of you, because two independent dated figures are still better than the single undated numbers most of this topic is covered with. But treat everything below as the shape of the job rather than today's quote, and expect the real figures to sit above them.
The two published ranges
| Source | Range | Average |
|---|---|---|
| Fixr, August 2022 | $225 to $850 | $450 |
| Bob Vila, December 2023 | $369 to $913 | $624 |
$174 between the averages, our subtraction, from guides sixteen months apart. Fixr adds a low end of $75 and a high end of $1,500.
Our reading, marked as ours: the gap is in the right direction for the dates, and the later guide is the higher one. That is consistent with price movement rather than disagreement, but we cannot prove it from two data points and we are not going to claim we can.
The figures that actually decide your bill
Fixr prices the job by where the fan goes and what powers it, and this is the most useful table published on the topic:
| Mount | Passive fan | Electric fan | Solar fan |
|---|---|---|---|
| Roof | $75 to $100 | $100 to $450 | $300 to $1,000 |
| Gable | $200 to $300 | $200 to $500 | $400 to $1,000 |
All six figures are installed costs. The spread runs from $75 to $1,000, which is more than the difference between the two publishers' averages, and it is a choice you make rather than a condition you inherit.
Two patterns worth naming, both ours. Gable mounting costs more than roof mounting in every column, because the fan goes through a wall rather than an existing roof plane. And solar costs roughly three times electric at the same mount, which buys you no wiring and no running cost, and is the trade this table makes visible.
Fixr adds the general version: a roof exhaust fan, also called a roof turbine, runs $75 to $1,000, and a gable installation $200 to $1,000. An energy-efficient model moves the whole job to $300 to $1,000 against $225 to $850 for a standard one.
What the parts cost
Bob Vila itemises, which is useful because the fan is only part of it:
| Item | Cost |
|---|---|
| Caulking and nails | $5 to $10 |
| Roof vents | $30 to $50 |
| Gable vents | $30 to $60 |
| Attic fan | $65 to $650 |
| Siding | $2 to $12 per square foot |
| Shingles | $17 to $40 per square foot |
The fan itself spans $65 to $650, which is nearly the whole of Fixr's installed range. Our reading: on a cheap passive roof unit the labor dominates; on a solar or high-airflow fan the equipment does. That is why the two publishers' averages tell you so little.
If the roof has no vents, the installer has to add them, and Bob Vila notes that a carpenter may be needed for roof modifications at $10 to $150 per hour. A humidistat, which runs the fan on moisture rather than only temperature, is $40 to $50 if bought separately.
Sizing it
Fixr gives the airflow rule:
| Attic size | Recommended airflow |
|---|---|
| 1,000 sq ft | 700 CFM |
| 1,500 sq ft | 1,050 CFM |
| 2,000 sq ft | 1,400 CFM |
Our arithmetic, marked as ours. Every row is 0.7 CFM per square foot of attic. Like the shared sizing tables we found on our radiant floor page and our furnace page, the table contains one rule with the multiplication already done. Unlike those, this one at least holds across the whole table and tells you something you can apply to an attic size that is not listed.
The city table, and what we do with it
Bob Vila prices seven cities:
| City | Installed cost |
|---|---|
| Chicago | $300 to $600 |
| Houston | $300 to $730 |
| New York City | $330 to $650 |
| Orlando | $350 to $550 |
| Boston | $430 to $850 |
| Seattle | $650 to $1,400 |
| Los Angeles | $500 to $1,450 |
Unlike the city table we rejected outright on our geothermal page, these rows are internally consistent: every one sits inside or near the page's own range, and the ordering is plausible, with the two west coast cities highest. We would still not use them as quotes, because a seven-city sample is not a regional dataset, but they are usable as a sanity check on an estimate.
Is it the right machine
Fixr makes the comparison most guides skip: an attic fan and a whole house fan are both installed in the attic and do different jobs. An attic fan exhausts the attic; a whole house fan pulls air through the living space.
Our note, marked as ours. We have not built a page on whole house fans because only one publisher we can reach has a cost guide for them, and we do not publish on one source. That also means we cannot give you a fair price comparison between the two here, and we would rather say so than quote one number against nothing.
What an attic fan is not is air conditioning. It lowers attic temperature and moisture, which reduces load on the system you already have. Our central air page covers the machine that actually cools the house, and our maintenance page covers keeping it efficient.
Before you get quotes
- Decide the mount and the power source first. Those two choices span $75 to $1,000 on Fixr's table.
- Ask whether the roof already has adequate venting. If not, add vents at $30 to $60 each, and possibly a carpenter.
- Ask for the fan's CFM, not its size in inches. At 0.7 CFM per square foot, your attic area gives you the figure to check against.
- Ask whether a humidistat is included. At $40 to $50 it is cheap, and it is what makes the fan run for moisture as well as heat.
- Treat any figure on this page as a floor. Both of our sources predate 2024, and we say so rather than presenting them as current.
Sources
- Fixr, Attic Fan Installation Cost, updated August 26, 2022 (the $225 to $850 range, the $450 average, the low and high ends, the mount-by-power-source table, airflow sizing, the comparison against a whole house fan)
- Bob Vila, What You Need to Know About Attic Fan Installation Cost, updated December 19, 2023 (the $369 to $913 range, the $624 average, the materials table, vent prices, the carpenter rate, the city table, humidistat cost)
Price figures are national US ranges from the sources above as of the date shown. Your local price depends on labor rates, permits and site conditions. Read how we get our numbers.