Common Places to Find Mold and Mildew on Your Roof

Mold or mildew on your roof is more than just an eyesore—it can be a sign of deeper moisture issues that may threaten the integrity of your home. Spotting and addressing mold early can help prevent costly repairs and protect your family’s health. Understanding where mold is most likely to appear on your roof can help you stay ahead of the problem.

One of the most common places to find mold is on the north-facing side of your roof. This area receives less sunlight, which means it stays damp longer after rain or dew. Mold thrives in moist, shaded environments, making this the perfect breeding ground.

Roof valleys—where two roof slopes meet—are also problem areas. Water naturally flows through these valleys, and if debris like leaves or twigs builds up, it can trap moisture and allow mold to grow.

Branches from overhanging trees that shade your roof prevent sunlight from drying out moisture, and falling leaves can accumulate and hold water. These shaded, damp zones are ideal for mold and mildew development.

Gutters and downspouts that are clogged or not functioning properly can also lead to mold problems. Overflowing gutters allow water to spill onto the roof or into the attic, soaking the underlying materials and creating a damp environment perfect for mold growth.

Poor attic ventilation can contribute to roof mold. When warm, humid air becomes trapped in the attic, it can condense on the underside of the roof deck. Over time, this moisture encourages mold to take hold.

Routine inspections and maintenance, including roof cleanings and proper ventilation, are the best ways to keep mold at bay. If you spot signs of mold and mildew, consult the professionals at Northern Illinois Seamless Roofing to assess the cause and recommend treatment.

Northern Illinois Seamless Roofing, Inc. is a local family-owned commercial roofing solutions company that has served the Mendota and surrounding communities for over 40 years.

For more information, contact:

Northern Illinois Seamless Roofing, Inc.

705 Illinois Avenue

Mendota, IL 61342

Ph: 815-539-5142

www.nilsroofing.com