The Different Types of Residential Ventilation Systems

For claims adjusters, understanding a home’s features is key to evaluating client inventories and replacement costs. One such crucial detail is the ventilation system. There are the four main types of systems available. Here’s a breakdown of how they work along with their strong points and drawbacks.

Exhaust Ventilation Systems

Ever flipped on the fan after a steamy shower or while cooking up a storm in the kitchen? That’s an exhaust ventilation system in action. This system works by using fans to pull out stale air, especially from areas like bathrooms and kitchens. As this old air is pushed out, fresh air naturally flows in from the outside. It’s a simple yet effective way to ensure the indoor environment remains fresh and free from excess moisture.

Pros

Exhaust ventilation systems offer a straightforward, cost-effective solution to maintaining indoor air quality. They are particularly beneficial in cold climates, where they excel at preventing moisture damage from the buildup of stale, humid air.

Cons

They can draw in pollutants along with fresh air. This includes radon and mould from crawlspaces, dust from attics, and fumes from attached garages or combustion appliances. In climates with warm, humid summers, the depressurization caused by these systems can draw wet air into wall cavities, leading to potential moisture damage. Additionally, they can contribute to higher heating and cooling costs because they don’t temper or remove moisture from air before it enters the house.

Supply Ventilation Systems

Supply ventilation systems are designed to introduce fresh air into a home. They work by using a fan to pressurize the unit, forcing fresh outdoor air inwards. As a result, indoor air exits, which balances the pressure inside the home.

Pros

Supply ventilation systems bring fresh air indoors. They allow for better filtration of the incoming air, and minimize outdoor contaminants, such as pollen and dust.

Cons

Introducing cold outdoor air directly into living spaces can lead to discomfort and increased heating demands, especially during harsh Canadian winters. Because this system pressurizes the home, warm air can leak through openings. This sometimes results in moisture accumulation and mould growth.

Balanced Ventilation Systems

Balanced ventilation systems provide fresh air to a home while simultaneously expelling stale indoor air. Unlike supply-only or exhaust-only systems, balanced systems introduce and extract equal amounts of each, maintaining a neutral pressure.

Pros

Balanced ventilation systems offer a comprehensive solution to home ventilation. They ensure consistent air quality by filtering incoming air and reducing contaminants. They can work well in all climates.

Cons

The initial installation can be more complex and costly compared to simpler systems. Additionally, balanced ventilation systems, like both supply and exhaust systems, don’t modify the temperature or remove moisture from the air before it’s introduced inside the dwelling. This can lead to increased heating and cooling expenses. Furthermore, to prevent cold air drafts during winter months, the system may need to mix outdoor air with indoor air before it’s circulated.

Energy recovery systems

Energy recovery ventilation (ERV) systems ensure a continuous flow of fresh air while optimizing energy efficiency. They provide both ventilation and energy recovery. ERVs transfer heat and moisture between the incoming and outgoing airstreams. This means that during cold weather, warmth from the indoor air is transferred to the incoming cold air and vice versa during hot weather.

Pros

ERVs stand out for their energy efficiency. Some manufacturers even claim that up to 99% of the heat energy from indoor air is transferred to incoming air. This efficiency creates a comfortable environment and leads to savings on energy bills. Furthermore, ERVs significantly improve indoor air quality by filtering out contaminants, allergens and other pollutants from the outside. They also play a pivotal role in controlling indoor humidity levels by transferring moisture between airstreams. This is particularly beneficial during hot, humid summers and dry, cold winters.

Cons

The initial installation of an ERV system is a major investment. They can also be noisy, which is a potential annoyance if installed near living areas. Maintenance is another consideration: more intricate ERV systems require more frequent upkeep, including cleaning or replacing filters. Lastly, it’s worth noting that ERVs don’t always lead to savings in mild climates.