How Ventilation & Insulation Prevent Mold Growth

Ventilation and insulation always go hand in hand. Together, they keep mold from forming in your attic. 

Bone Dry Roofing – West, your trusted roofer, explains how below: 

How Ventilation & Insulation Prevent Mold 

Mold needs three things to grow: humidity, high temperatures and biodegradable material. Proper ventilation and insulation prevent mold by managing the first two factors: humidity and high temperatures. Adequate ventilation lowers indoor humidity levels by removing warm, humid air from your house, while insulation keeps indoor temperatures low to prevent air from reaching dew point temperatures and condensing into droplets. 

By preventing warm, humid air from condensing into droplets, adequate ventilation will also ensure that your insulation doesn’t lose its R-value (R-value indicates your insulation’s ability to prevent heat transfer). When insulation gets wet, it can lose up to 40 percent of its R-value. 

How Much Ventilation & Insulation Does Your Attic Need? 

As a general rule, there should be one square foot of ventilation for every 300 square feet of ceiling space in attics with a vapor barrier. But for attics without a vapor barrier, there needs to be one square foot of ventilation for every 150 square feet. As for insulation, most contractors would recommend installing insulation with an R-value of 38. 

Keep in mind that different types of insulation have different R-values and are only suited for certain types of applications. For instance, if you’re adding insulation to your attic, loose-fill and sprayed foam insulation are great for unfinished attic floors and new wall cavities. The same goes for air vents: not all vent types can provide the same level of ventilation. 

To learn more about your insulation and vent options, consult a local roofing contractor. Since they’re more familiar with the local climate and building codes, they can make better recommendations. 

Bone Dry Roofing – West offers a wide range of professional roofing services. Call (970) 364-7996 or fill out our contact form to schedule an inspection.