Clearing the Air – Considerations for Attic Ventilation

This article supports Air Vent's longstanding recommendations to roofing professionals when considering residential attic ventilation:

1) Keep the airflow balanced with INTAKE and EXHAUST regardless if you use the 1/300 or 1/150 ratio.
2) Increase the amount of overall ventilation for roofs 8/12 pitch and steeper (all of Air Vent's calculation tools have this built into their logic)
3) Having more EXHAUST than INTAKE is problematic.


pdf small Read the full article - "Clearing the Air"




The effects of household humidifiers on attic moisture accumulation

A word of caution about humidifiers


Thanks to an attendee of the Air Vent “Attic Ventilation: Ask the Expert Seminar™” we have this word of caution about humidifiers to share with you: Learn how homeowners can better manage their household humidifiers to avoid an excess buildup of moisture and condensation in their attic. Common consumer-level household humidifiers can add over 15 gallons of moisture to your home which can hinder attic ventilation performance.


pdf small Read more about humidifier management, and recommended humidity levels for optimal attic ventilation
(Includes Attic Condensation Checklist)



Humidity and Condensation




2018 International Residential Code for One- and Two-Family Dwellings

Every 3 years the International Residential building Code (IRC) releases code updates. 2018 is a cycle year. Below is the attic ventilation section. Key notes/changes:


  • The minimum amount of attic ventilation remains 1/150 (1 square foot of Net Free Area for every 150 square feet of attic floor space. Attic floor is defined as length x width FLOOR of the attic).

  • The amount of ventilation can be reduced to 1/300 (in effect 50% less) BUT 2 conditions must be met effective 1.1.18. Previously only 1 condition had to be met. The ARMA Ventilation Task Force pushed the IRC for this change. (See below).

  • Renewed for 2018 is the requirement that “vents must be installed according to the vent manufacturer.” This includes: Don’t Mix Exhaust, give the exhaust vent proper intake, etc.


pdf smallRead the full 2018 Bulletin Here

Understanding Product Certifications

what do attic ventilation product certifications mean to our customers?


A closer look and understanding/appreciation for what the various product certifications mean in the market. Specifically:

• Miami-Dade County
• UL
• Florida Building Code
• Wildland Urban Interface


pdf small Read more about understanding product certifications 




How Roofing Contractors Can Help Clients with Insurance and Attic Ventilation Upgrades

After the Storm

"After the Storm"

The weather forecast looks poor. Strong winds, heavy rain and the possiblity of hail — golf-ball sized or larger — could hit the area. The storm strikes, and many houses are damaged to the point of roof replacement is necessary. Homeowner's insurance will pay the cost of the new roof and the attic ventilation, but what if the vents that were in place don't meet code requirements? Will homeowner"s insurance pick up the tab? And what if the contractor recommends a better, more efficient way to vent the attic different than the vents that were in place? Will insurance pay for the upgrade? 


Some roofing contractors in storm-prone markets are successfully convincing homeowner's insurance to pay. Here's how....


PDF Read the full article



Air Vent Contractor LocatorOur exclusive Contractor Locator will allow you to find contractors in your area who can assist with Air Vent product installation—including solar attic fans and skylight tubes. Click the link below to register and get started.


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