how to improve
basement
ventilation

In most homes, the basements are the dingiest and dankest parts of the house,
as ventilation is very much not a priority. If your home has your washer and dryer
(and other appliances such as a water heater) in the basement, then the
combined heat and humidity from these may lead you to assume that your
basement is always full of moisture.

However, that’s not necessarily the case and it doesn’t need to cost a ton to
improve your basement’s ventilation.

WHY VENTILATE A BASEMENT?

There are four main reasons why you
might want to improve the ventilation
in your basement:

DAMAGE

Moist air can cause damage to furniture, appliances, and other materials (such as carpet) in your basement. Moisture in the air forms as condensation on the surface of objects, which is quickly absorbed, eventually causing the object itself to become damp.

To put it another way, if you wouldn’t pour a bucket of water on an object, then you shouldn’t leave it in a poorly-ventilated basement.

HUMIDITY

If you live in a humid area, such as parts of the southeastern corner of the United States, then ventilating your basement will be a part of the wider HVAC process of your home.

Basements tend to be a cooler part of the house, so ventilating it (and dehumidifying it) will give you a space to hang out in during the heat of the summer. Indeed, if you are planning any sort of basement conversion, then ventilation is essential.

MOLD

A poorly-ventilated basement can be a haven for mold and mildew. According to the Center for Disease Control, mold is common in environments where there is a lot of moisture. The most common indoor molds are Cladosporium, Penicillium, and, Aspergillus.

Each of these has the capacity to impact the health of those who come into contact with it, as well as cause structural damage to your home if left unchecked.

RADON

Almost every home has some level of radon present in the basement. Radon is a gas that is a by-product of the decay of uranium and can be harmful in large enough concentrations. As uranium decays in the rocks and soil around and underneath your home, the radon gas is often vented into your basement.

In most states, you can send away for a free radon testing kit, which will tell you how much radon is present in your home. If you have radon in your home, you may be legally mandated to vent it.

NATURAL
METHODS

Here are some natural remedies for ventilating a basement.

If you have windows in your basement, then making sure to use them is by far the easiest way to ventilate your basement.

INSTALLING WINDOWS

If you do decide to install windows, you should remember the following rules:

They should be placed in a location where it’s easy to open and close them

They should be protected from the impacts of extreme weather

The more windows, the better, to allow for greater airflow.

EGRESS WINDOWS

Egress windows are windows that are big enough for you to exit through in case of an emergency (hence the name). Installing egress windows is a much larger project than regular windows, as their installation often involves cutting through part of your home’s foundation.

For the installation of a full egress window and a window well in a basement where there were previously neither can cost up to $8,000.

In the case of both regular and egress windows, you can choose frames that have ventilators fitted in them. This will allow fresh air to pass through your basement even when the windows are closed.

MECHANICAL VENTILATION

In some extreme cases, the natural method
may not be enough to ensure that a
basement is well ventilated enough. In
these instances, you will need some form
of mechanical ventilation.

In some cases, mechanized systems contain humidity sensors, meaning that you don’t have to monitor the situation in your basement – the system will be self-regulating. The downside is that mechanical systems are often more expensive to install.

FORCED AIR SYSTEM

A forced-air system is a form of HVAC system which is the most commonly used system in the United States. The system works by drawing in cold air from inside the home, passing it through an air filter and then using a furnace to heat it. This process will continue until the air matches the desired temperature as set on a thermostat.

The benefit of this system for basement ventilation is that you can connect it to your home’s existing forced air system. Many forced air systems contain dehumidifiers, which will mean that the air being pumped into your home is relatively moisture-free.

The cost of installing a forced air system in your home will come in somewhere
between $1,000 and $1,500.

EXHAUST FANS

An exhaust fan works by pushing air out of your basement. This removes the stale air from inside, and the pressure differential forces fresh air from outside to come in.

You can run this option in conjunction with a ventilation fan on one side of the basement and an exhaust fan on the other; however, in many cases (such as with a small basement), an exhaust fan alone should suffice.

RADON MITIGATION SYSTEMS

There are a variety of options for removing radon from your basement. The best ones are those that remove 50-99% of radon. The comparison table below will give you the key financial information to help you make your decision.

METHOD	INSTALLATION COSTS (by a contractor)	ANNUAL OPERATING COSTS
FAN-BASED SUB-SLAB SUCTION	$800 - $2,500	$225 - $500
DRAIN TILE SUCTION	$800 - $1,700	$50 - $200
SUMP HOLE SUCTION	$800 - $2,500	$50 - $250
BLOCK WALL SUCTION	$1,500 - $3,000	$150 - $400

Before you pursue any of the above options (or any other methods of removing radon from your home) speak to a professional, as they will be able to give you advice based on your specific circumstances.

THE SIMPLE OPTION

Of course, not all ways of improving ventilation involve cutting openings in your foundations or installing advanced systems into your home.

If your goal is simply to provide a more comfortable space while you are doing laundry, or if your basement serves as a home office, you may simply be talking about improving the air quality. In those instances, you can take a set of far simpler actions that will do exactly what you need without breaking the bank.

DEHUMIDIFIER

Dehumidifiers are great and simple way to remove moisture from a basement. You just have to plug them in and let them do their work. You can rent an industrial sized dehumidifier, which will dehumidify around 18 gallons or 144 pints per day, for around $200-$250 for a week.

Purchasing a non-industrial dehumidifier, which will dehumidify about half of that amount each day, will cost between $200-$300. If you go this route, you will need to regularly empty the dehumidifier’s water reservoir. For reviews of popular dehumidifiers, check out our Best Dehumidifiers for Basements guide.

FAN

A box fan will provide a powerful way that you can move air around within your basement. If you leave the basement door open, a box fan may be sufficient to circulate air from your basement throughout the rest of your home. This will provide enough air refreshment to significantly improve the comfort level within the space.

Of course, a box fan will not work if you have a more serious issue within your basement, such as mold or water damage.

Ultimately, basement ventilation is self-evidently beneficial. From the simple comfort, you feel from entering a basement that is not dank and humid, to ensuring that your furniture and appliances last longer – making sure part of your house isn’t a haven for mold are all benefits.

The only limitation is your budget and your inclination to do the work (or pay someone to do it for you). Not only will you make your home more livable, but you’ll potentially add value to your home, meaning you should see it as more of an investment – if not just in your quality of life.

how to improve basement ventilation