Is Your Home Breathing? The Why and How of Roof Ventilation

roof ventilationIn a previous blog, we looked at the importance of insulation in a roofing system. There are plenty of benefits in having quality work done to ensure that either warm or cool air is being kept in to increase your comfort in the home, depending on the season. What we might believe, therefore, that it is necessary to pack the attic or roof deck with as much insulation as possible, case closed.

The more material present, the higher the R-value, which in some ways does mean a more efficient house; unfortunately, this idea is a bit misguided. While having a good insulating product is extremely important, there needs to be another vital element at play to ensure that your home’s roof remains in good order and functions well.

Roof Ventilation: Count the Benefits

Roof ventilation: not many people put a lot of thought into whether or not their roof can “breathe” properly,  but this is of major importance when it comes to a roofing system’s overall health. Read on for the three main advantages.
attic space

  1. Gets rid of excess heat – In warm weather, excess heat can build up in the roof attic during the day and then radiate into the house. If not removed, that heat is trapped inside the attic space after sunset, continuing to heat the home. Proper roof ventilation is needed to effectively remove heat from roofs during the summer months. This is not only desirable for comfort but proper ventilation is necessary in order to not void your shingle warrantee.
  2. Banish excess moisture – In the winter months, and often at night, generally, moist air from the house (from hot showers, cooking, etc.) travels into the roof area, especially in older homes that don’t have proper vapor barriers, where it hits the cooler underside of the roof and condenses. It then falls back onto the ceiling, and can cause mold and mildew to grow. Excess moisture can also have a detrimental effect on insulation and construction materials, causing them to deteriorate more quickly.
  3. Do a number on dust – Dust enters through small gaps in the roof structure and can create a dirty and messy situation for any tradesmen or home handyman who needs to access the roof space for repairs. It never hurts to keep a home’s dust level under control with respect to the health of its occupants, either, especially for those with asthma or other breathing problems.

Why Focus on Roof Ventilation?

A character improves energy performance of a houseThe short answer to why roof ventilation is important is climate control. Vancouver is known for its bipolar weather forecasts. In the span of a week, we could have pelting rain, brilliant sunshine, or blustery wind, and your roofing system has to be capable of handling it all in stride.

  • In the Cold – Good roof ventilation will help to maintain the heat within the house and work to prevent ice dams that can build up underneath shingling and leak through the roof.
  • In the Heat – Roof ventilation allows hot air to rise through and alleviates the stress put on an air conditioning system, which will bring down electricity costs.

Two Main Approaches to Roof Ventilation

This doesn’t mean you should head up to your attic and start punching air holes through the ceiling; the process of proper roof ventilation is a little more complicated. When it comes to roof ventilation, there are a couple of different ways to approach the process, depending on what part of the roof is being worked on.

  • Attic ventilation: The basics of attic ventilation involves making sure the space between the insulation and the underside of the roof membrane or shingles is properly ventilated. One of the most common mistakes is putting in insulation that blocks the ventilation openings.
  • Roof deck ventilation: This involves creating space between the shingling and roof deck in order to fit a special baffling for ventilation. The air enters slits at the bottom of the roof that filter up and exit through spaces at the peak.

vancouver-rooferAs a renovator Doug did many rot repairs which gave him a good understanding of where and why buildings leak, and how to prevent it. He realized the need for a different approach to roofing; one that educated the customer enough to make good decisions. With better trained installers and a quality inspection process Absolute Roof Solutions was born…” Read more.
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