Your Roof’s Ventilation System Could Be Costing You Money

One of the most important aspects of the way your roof is designed and built is proper ventilation. You simply cannot over-estimate its importance. Improper ventilation allows formation of condensation, moisture accumulation, and damage to the roof deck and will eventually lead to the instability of the roof. Your family’s health can also be affected by improper roof ventilation.

What Will Happen If A Roof Doesn’t Have Proper Ventilation?

The industry standard for roof ventilation to provide 1 square foot of intake ventilation and 1 square foot of exhaust or outflow ventilation for every 300 square feet of attic space, provided the area is insulated with a vapor barrier.  If the area is insulated without a vapor barrier, the requirement doubles.

Proper ventilation of the roof and attic of a home will achieve several important functions:

  • It makes your attic space cooler
  • It makes your home more energy efficient
  • It prevents condensation and accumulation of moisture on the inside of the roof deck, and will prevent rotting of the roof deck
  • It will reduce the risk of fire

Several types of vents can be used to adequately ventilate your roof. Roof ridge vents are placed along the ridge line of the roof. Ridge vents are used for exhaust or outflow of moisture, heat, and stale air. Soffit vents and Eaves are placed at the lower extremes of the roof and provide the intake ventilation.  If you live in an older home, your roof might not be constructed for roof ridge or soffit vents. Older homes were not built with the tight seals of today’s houses. There were cracks and openings around windows and doors, chimneys and other openings.  These cracks and openings allowed fresh air to flow into the house.  On the principle that hot air rises, the accumulated heat and moisture would rise to the attic and out the roof vents.

Without adequate ventilation, moisture rises with the hot air and forms condensation on the inside of the roof deck. This moisture is released into the air inside the house from bathing, cooking, plants, laundry and other causes.  When the condensation forms on the roof deck, it can begin to rot the wood. This will introduce mold spores into the air, as well as damaging the wood. If the problem is not repaired, the result can be the deterioration of all or part of the roof deck. Not to mention the creation of unhealthy air inside the house.

In our increasingly airtight homes, the importance of proper ventilation in roof construction cannot be over-stated.  It is important to take the time and do some research to understand the ventilation needs for your home in your region and what to do to best meet those needs.

It is very important that your roof has ventilation according to code specifications and that the ventilation system is working properly. The best way to make sure your ventilation system is installed properly is to hire a Minnesota roofing contractor for a roof inspection.