Active Vs. Passive Roof Ventilation

You know that ventilation in your home is important not only for the health and resiliency of your roof and attic, but you and your family as well. But do you know the difference between active and passive roof ventilation, and which one is right for you?

Ventilation methods can be either active or passive ventilation; however, under each type of ventilation, there are many subcategories, which makes deciding what type to get challenging. In the following article, we will try and narrow them down for you and explain each type of ventilation system, so that you can decide which is best for you and your home.

Passive Ventilation
Passive ventilation is a method by which no forced air is used, like in a fan. Instead, passive ventilation systems utilize the wind along with rising heat force, called heat buoyancy or convection, to properly ventilate an area. For roof and attic ventilation, passive ventilation usually includes ridge vents that are located on the top of a roof and soffit vents located underneath, which allow cool air to move in through the soffit vents and push the hot air out through the top of the ridge vents.

Passive ventilation advantages:

• Uses no energy like electricity or fossil fuels to ventilate, instead, it uses only natural forces. This saves money on energy bills and is a greener solution to ventilation.
• Requires very little maintenance (if any).

Passive ventilation disadvantages:

• Passive ventilation may not be enough to properly ventilate an area, especially in complex structures.
• May require passive ventilation to be considered in the construction of the building for best results.

Active Ventilation
Active ventilation is a system that uses powered machines like fans to push and circulate air in order to ventilate a space. Active ventilation systems can be used pretty much anywhere, whereas passive ventilation is less effective in complex structures. Active ventilation in a roof or attic may look similar to passive ventilation systems, with soffit and ridge vents, except that active systems have the addition of a fan to push out hot air and pull in cool outside air.

Active ventilation advantages:

• Very effective, regardless of weather conditions.
• Can effectively ventilate complex structures.

Active ventilation disadvantages:

• Uses energy, unlike passive systems.
• Costs more to run and requires more regular maintenance.

Conclusion
The advantages and disadvantages of both passive and active ventilation systems are quite clear. Passive ventilation systems might be fine for you if you have a simple home with an open attic and can easily install or use your soffit and ridge vents without any ventilation issues. However, if passive ventilation just doesn’t cut it for your home, then active ventilation will certainly make sure that air is circulating in your attic and that your home is ventilated properly.

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