Home Ventilation: Whole-House Systems And Other Options

Efficient house ventilation is important in any modern home. New-construction homes are designed to be air-tight, meaning the indoor air can grow stale from exhaled carbon dioxide as well as internal contaminants like allergens and mold. A home ventilation system brings fresh, new air indoors and removes old, stale air. Adding the right mechanical ventilation system is essential for the indoor air quality of any home.

What Is House Ventilation?

House ventilation refers to the movement of air between the inside and outside of your house. Whole-house ventilation is, for many, an important part of having a healthy home. Many modern homes are so tightly built that air doesn’t move as freely through cracks in the walls as it does in older homes, so homeowners may choose one of four types of ventilation systems: exhaust, supply, balanced or energy recovery/heat recovery (ER/HR) ventilators.

Why Does Ventilation Matter?

Several health concerns motivate homeowners to consider house ventilation. Allergens, pollution from modern building materials, and air pollutants from outdoors can cause discomfort and illness. Proper ventilation is important to ensure those pollutants don’t enter your home and cause short- or long-term health problems.

Old Vs. Newer Homes

Older homes and newer homes are different in terms of air exchange. Old houses are generally known to be “drafty.” This draftiness is a result of air flowing in between small gaps in the construction of the home. Modern homes have batt insulation, caulk tubes and other precautions that prevent airflow from outside to inside the home.

Types Of Whole-House Ventilation Systems

Whole-house ventilation systems come with several pros and cons for homeowners, differing based on the climate, installation process and cost-effectiveness. Check out the advantages and disadvantages of exhaust, supply, balanced and ER/HR ventilation systems.

A whole-house ventilation system can make a significant difference in how comfortable you feel in your home. While altering your current system or building a new one from scratch can be expensive, you might have the option to tap into your home equity to get the job done.

Exhaust Ventilation

Exhaust systems use exhaust fans in pollutant-creating areas like kitchens, bathrooms, basements and attics to blow polluted air out of the home. New, fresh air comes in through intentional passive vents or leaks in the walls.

Because the outdoor air enters through passive vents, humid climates can produce moisture that settles in those cracks and crevices. This moisture can encourage mold growth, which you’ll need to remove. This method of ventilation therefore isn’t recommended for humid areas.

Since air is just coming inside through little cracks, it can bring in pollutants like radon, mold, dust and pollen. This system also doesn’t alter the temperature or humidity of air seeping through these small cracks, which means your heating and cooling system will have to work harder to get the new external air to the proper temperature.

Supply Ventilation

Supply systems are basically the reverse of exhaust systems. They use a fan to blow new, fresh outdoor air into a building, then push the old air out of small cracks or passive vents in your home.

Using a fan to blow new air inside your home helps control the flow of incoming air. You can better filter out pollutants, pollen and dust by adding filters to the fan and adjusting the humidity of air coming in. This will help to reduce heating and cooling costs compared to an exhaust system.

Supply systems don’t work great in cold climates. As warm, heated air slowly leaks out of a home into the cold exterior, this change in temperature and humidity can cause moisture to condense, especially in attics, leading to mold and rot.

Balanced Ventilation

A balanced home ventilation system is a combination of exhaust and supply systems with two fans and two systems of ducts. It exhausts air from rooms that cause more pollutants – like kitchens and bathrooms – and also blows fresh air into rooms like living rooms and bedrooms. These systems filter out pollutants at the ventilated point of entry.

Because of the dual fan system, balanced ventilation works well for all climates. However, balanced ventilation systems are twice as expensive to install and operate since they’re basically two systems.

ER/HR Ventilation

Energy recovery systems are designed to be as energy-efficient as possible. These systems use heat exchangers to transfer heat in a way to maintain constant internal temperatures and reduce the need for heating and cooling as much as possible. Basically, they capture the temperature of old air as it’s blown out of the building and transfer that temperature to the new air as it’s blown in.

Heat recovery ventilators transfer heat from inside to outside the home to keep the temperature balanced. ER ventilators transfer heat as well as moisture, making these ventilators better for humid climates.

ER/HR ventilation systems are complex and the most expensive to install and maintain. They require a lot of technical expertise that might be difficult to find in some areas.

Other Home Ventilation Options

In addition to whole-house mechanical ventilation systems, other house ventilation options are worth keeping in mind, and we’ll explore them below. 

Stack Ventilation

Stack ventilation, also called the chimney or stack effect, is a method of natural ventilation that uses two air vents – one at the lower level of your house to allow fresh air in, and one on a higher level to remove stale air – to create airflow throughout your home. Stack-effect ventilation works to naturally circulate air based on changes in air pressure, density and temperature levels between the inside and outside of your home.

Trickle Ventilation

Trickle ventilation is another form of natural ventilation that uses small air vents, or trickle vents, above your windows or doors to allow small amounts of air to circulate through your home. This method can minimize drafts and reduce air pollutants coming into your house.

Spot Ventilation

Spot ventilation is a mechanical ventilation system in one area or spot. Spot ventilation uses exhaust fans to circulate air and remove pollutants and moisture, and you can typically find them in your bathroom or kitchen. Because this ventilation system is limited to specific areas in your home, it’s not the best option for whole-house ventilation.

Are The Energy Costs Worth The Benefits Of A Home Ventilation System?

The houses that generally need ventilation systems the most are newer, more airtight buildings that tend to be much more energy-efficient than older homes that don’t need ventilation. The appliances involved are likewise energy-efficient, meaning that installing a ventilation system will enhance health while still allowing building owners to reduce their carbon footprint.

Is House Ventilation Synonymous With Air Purification?

Major differences exist between ventilation and air purification. Air purification systems filter air and remove contaminants from it. On the other hand, air ventilation is simply the distribution of fresh air to the various rooms of a home. Ventilation helps find a balance in air quality, temperature and humidity, keeping air from going stale. However, if external air is very polluted or contaminated, ventilation won’t remove those pollutants – only purification can.

The Bottom Line: Tight Homes Need A Breath Of Fresh Air

Modern homes are airtight – which is great for many reasons. However, this requires that you stay on top of your home’s ventilation system to ensure the health of your home and those who live in it.

If the ventilation options you find to be the best fit for you are on the pricier side, you might consider financing. A cash-out refinance can be a terrific way to leverage your home equity to get favorable interest rates and kickstart a cycle of home value and home equity increases. If that sounds good, why not work toward getting a cash-out refinance, starting today?