How Does Humidity Affect Roofing Systems?

High indoor humidity affects your home in many ways. It can make your home feel uncomfortable, it can damage decor and furniture and can encourage mold and mildew growth. In today’s post, local GAF Master Elite® roofer Ken Morton & Sons discuss how high humidity levels affect another part of your home: the roof.

Humidity Damage

Warm and humid air tends to rise and collect in the attic. If not vented properly, it can accumulate as condensation and cause damage to the roof’s structural support, which is mostly made of wood and metal fasteners. Mold may also grow on these parts. Wood rot may also happen to the roof deck, which may further weaken the structure as the laminated plywood layers separate.

Where Does the Moisture Come From?

There are many sources of moisture from the house, which can raise relative indoor humidity levels. Activities such as cooking, bathing, and washing laundry and dishes release moisture into the air, usually in the form of steam. If your home has a traditional hydronic heating system—a home heating system that utilizes hot water running through pipes—it may also release steam from the basement. Leaky plumbing can also release moisture that eventually evaporates and mixes with the indoor air.

How to Protect Your Roof from High Humidity

We recommend keeping an eye on your home’s relative indoor humidity levels using a hygrometer. The ideal level is between 30% and 50%. The following are some of the things that you can do to maintain indoor humidity levels and reduce the amount that rises into the attic:

Ensure proper ventilation — Your home has two main types of ventilation, both of which should be working properly. The return registers connected to the HVAC vents take away warm air and moisture from the indoors using blowers and replace them with fresh, cool air (or warm air, during the winter season). Attic ventilation, which consists of ridge vents for exhaust and soffit vents for intake, provides ventilation to the attic. Improper attic ventilation can be addressed by roofing contractors on existing roofs.

Install dehumidifiers — Dehumidifiers absorb excess moisture in the air. While there are standalone units that can be purchased for individual rooms, whole-home dehumidifiers are far more effective and can help significantly reduce the moisture that would otherwise end up in the attic.

Ken Morton & Sons is your leading provider of roofing and siding repair and installation services. Give us a call at (856) 582-8800. You can also fill out our contact form to schedule an appointment. We serve customers in Woodstown, NJ, and the surrounding communities.