Open vs. Closed Roofing Valley: Which Should You Choose?

Roofing, Siding, Window, Door And Gutter Services From Montgomery To Anne Arundel Counties

Every roofing component, no matter how small or seemingly inconsequential, affects the performance of the whole system. This is why it’s important to choose high-quality features and products.


In this article, trusted roofing contractor Winfield Builders talks about roof valleys, specifically the difference between open and closed systems.

What Is a Roof Valley?

The valleys of the roof are the areas where the different planes intersect. Due to their construction, valleys are vulnerable parts of the roof, especially if they were not properly installed. There are two types of valleys — open and closed — and it is paramount that you choose the option that can best direct water runoff away from your roof.

Open Roof Valley

It’s important to understand how a roofing company installs a roof. First, an underlayment is installed over the roof decking. The underlayment can be coupled with a self-adhering ice and water shield, or it could be fortified into a heavy-duty, durable layer. A pre-bent metal valley lining — or an open valley — is installed after the underlayment. The material can be any metal that’s resistant to acid rain.

Closed Roof Valley

With a closed roofing valley, a metal lining is not necessary. This type of valley features the same asphalt shingle material installed on the rest roof, resulting in a smoother, more seamless look. Closed roof valleys are very popular among homeowners for this reason.

Open valleys can help your roof shed ice and water more efficiently, but closed valleys are faster, easier and generally cheaper to install. It’s all a matter of determining what you’re looking for in a roof.

You can count on Winfield Builders for a well-constructed roof, whatever the material or style. We also offer high-quality siding products and services. Call us today at (301) 329-8295 to get a free quote. We serve multiple areas in Maryland, including Annapolis and Columbia.

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