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Airflow Calculation: A Key Component of Roof Replacements

If you’ve started doing your research on roof replacements, you probably have a pretty good grasp on the steps required to complete the project.

However, you have to know the signs of roof replacement rather than repair. You need to decide which material is best for your shingles. And you need to evaluate quotes to choose the best contractor for the job.

Here’s one key contractor differentiator that most homeowners never think of—airflow calculation for proper rooftop ventilation.

The Importance of Ventilation for Your Roof

Take a quick look at your roof and you’ll notice an assortment of vents. This system of intake and exhaust vents regulates airflow through your attic and below your roof, providing protection for your roof.

The combination of petroleum and fiberglass in asphalt shingles and attic insulation has made airflow regulation a critical aspect of roof design and installation. Without a way to manage the airflow, you risk sacrificing the longevity of not just your roof, but of your home itself.

With proper rooftop ventilation, you unlock benefits such as:

  • Greater Longevity of the Roof: In the winter, consider the impact that ice damage has on your roof and home. Although it may be cold outside, your roof and attic can be much warmer then the ambient temperature. The warm air trapped in the attic will heat snow and then refreeze it when temperatures drop. When ice builds up at the edges of your roof, moisture can accumulate in your attic and lead to widespread water damage. Proper ventilation lets this warm air escape, keeping the equilibrium below your roof. And as a result, your roof lasts as long as the materials are designed to.
  • Reduced Energy Costs: Warm air rises, so in the summer months, your attic and roof get very hot. If the air gets trapped, your central air conditioning will have to work overtime to cool the home. And worse yet, trapped warm air in the attic can cause uneven cooling throughout the house. Proper ventilation lightens the load on your AC and cuts energy costs.
  • Moisture Protection: Moisture buildup leads to water damage in the attic and damaged and ineffective insulation. As water seeps through insulation, you can start experiencing leaks in your ceiling, damaging the interior of your home.

It’s great to understand the importance of rooftop ventilation and airflow calculations. However, you shouldn’t have to be the one recognizing potential problems. That’s why airflow calculations are a great way to separate the good contractors from the bad.

What You Need to Know About Airflow Calculations

The amount of ventilation needed for your roof is dictated by an airflow calculation. Contrary to popular belief, simply having vents across the roof doesn’t mean you’re well ventilated.

Instead, you need someone to determine the square footage and net free area of your roof and attic. These numbers will help determine the volume and balance of intake and exhaust vents.

This is something that every roof replacement contractor should include in your proposal. Without it, you’re simply taking the provider at their word and assuming that the ventilation will be done properly. This could lead to regulatory problems somewhere down the line if a permit is skipped and a future roof inspector finds that the roof wasn’t installed properly.

Use an airflow calculation as a barometer for good contractors. If your proposal includes this granular detail, it’s more likely you can trust the contractor for your roof replacement.