Open vs. Closed Roof Valleys Explained

If you are planning a residential roof replacement, it helps to understand what roof valleys are. A valley is where two roof surfaces intersect forming a v-angle and create a channel that allows water to run off the roof. When not done properly, this is where leaks could happen. There are two basic valley types: the closed valley and the open valley. We discuss their differences in this post.

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The Closed Valley

In closed roofing valleys, the roofing shingles are continuous over the valley. This is the less costly option because no extra materials are needed in the areas where the roof intersects. Also, some people prefer this type because there is no visible flashing in between the valleys.

The Open valley

In an open valley, a metal lining is installed on top of the underlayment, adding more protection in the valley. Then the shingles are installed on the roof, extending to the metal lining but not completely covering the lining up. The metal lining will be visible, but you can ask roof repair experts to use flashings similar in color to the shingles if you do not want them to stand out.

Thanks to the extra layer of protection, most contractors prefer the open valley installation. It also sheds water and ice faster and will help minimize granule loss from the asphalt shingles. Open valleys could potentially cost more, particularly if there are multiple valleys which would ultimately require more material.

If you are looking for roofing contractors that can provide you with excellent service, you can turn to Sully-Jones Roofing Company. Since 1952, we have been providing high-quality service in California. We are fully licensed and insured, and we have earned an A+ Rating from the Better Business Bureau. We offer both residential and commercial roofing services.

Give us a call at (619) 444-0150 or fill out our contact form. We serve clients in El Cajon, CA, and nearby areas.