Blog Category - Seasonal

Seasonal tips and articles on roofing, windows, siding, gutters, and solar from our expert Colorado contractors. Spring, summer, fall, winter and holiday tips included. 

Summertime Roof Prep Is Your Attic Properly Ventilated - J&K Roofing

Summertime Roof Prep: Is Your Attic Properly Ventilated?

How Does Ventilation Work?

The primary function of ventilation is to allow air and moisture to escape out of the home. Heated air rises naturally, and a ventilation system takes advantage of this phenomenon by incorporating hot air exhaust vents at the highest point of the roof (the peak) to allow the hot air to escape.

By contrast,  are placed at the lowest part of the roof (under the eaves), allowing cool air to enter. In the summer, this airflow helps keep the home cool and avoid excess moisture build-up.

Attic Ventilation Diagram - JK Roofing


Diagram courtesy of

Signs of Poor Ventilation

One of the biggest signs your attic may not be properly ventilated is overheating in the summer. Poorly-ventilated attics can exceed 150 degrees Fahrenheit when temperatures outside are in the 90s (not uncommon in the Colorado summer). Not only is this inconvenient for the homeowner, but it can also lead to other problems:

1. Roof Damage

Attics with insufficient ventilation tend to trap heat and moisture. This can lead to warping or sagging of the decking which supports your roof. Your shingles will also take a beating, as the excess heat can effectively “bake” them and cause them to crack and split.  You may also notice early granule loss or curling at the edges.

2. Water Damage

  • Mold/Mildew: trapped moisture leads to mold and mildew, which can result in costly structural damage. If you see or smell mold in your attic, it is a sign that your ventilation needs to be inspected.
  • Rust: over time, moisture can also cause metal structures to rust and weaken, resulting in structural instability.
  • Pests: warm, damp areas are attractive to rodents, insects, and other pests. You may hear scratching noises or notice droppings, gnaw marks, or “nests” insulation if you have a pest problem.

3. Higher Energy Costs

Your air conditioning system will have to work overtime to cool an improperly ventilated house. This can result in significantly higher energy bills (up to 40% higher) and you may find you have to replace your HVAC system prematurely.

4. Poor Air Quality

Air that is not circulating in and out of the attic efficiently is not filtered and can reduce the overall air quality of your home. If mold and mildew are present due to excess moisture, this further compromises the air quality and can potentially be dangerous to your health.

What to Do If You Suspect Poor Attic Ventilation

Ventilation is important year-round. It is a crucial step in maintaining the longevity of your roof and the integrity of your home overall. If you notice any signs that your roof’s ventilation is in need of repair, contact your local roofer for a professional inspection.

J&K Roofing provides free roof inspections (including ventilation) in the Denver Metro, Front Range, Colorado Springs, and Northern Colorado areas. Contact us today to make sure your attic and roof are ready for the hot summer months ahead.

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