Closed And Open Valley Roof Systems: What’s The Difference?

January 13, 2023

Protect Your Home With The Right Roofing Solution

In Houston, TX, it’s crucial to choose the right roofing system for your home or business. When choosing between closed and open valley roof systems, you should consider several key differences before making a decision. Each has its advantages and disadvantages, so understanding the differences can help you make an informed choice.

When torrential rains and heavy winds hit Houston, it is important to have a roof that can handle the beating. To protect your home or business from the harsh elements, you need to choose a system that will provide superior protection. Closed and open valley roof systems are two of the most popular roofing options available in Houston, TX.

Let’s take a look at the primary differences so you can make the best possible choice for your roof.

Closed Valley Roof Systems

A closed valley roof system is one where the shingles on either side of the roof planes are overlapped or “closed” to create a waterproof seal. This shuttered valley is characterized by a single valley that is completely sealed on both sides with metal flashing.

The roof is constructed by running shingles from one side of the peak to the other to create a continuous seal that prevents moisture from infiltrating the attic space beneath it. This creates a system where water runs from one side to another without collecting in large pools or puddles.

The presence of shingles over the channel also helps direct rainwater away from vulnerable areas such as soffits, fascia boards, and window frames. Additionally, because water doesn’t collect in these channels, these box valley roofs are less prone to future leaks or damage due to standing water or ice accumulation.

The downside is that these enclosed systems require more maintenance as they tend to wear down faster because they do not have adequate ventilation or run-off outlets for excess water.

Open Valley Roof Systems

Instead of running shingles continuously across the peak, the open valley roof design uses valley flashing made out of metal.

Open valley systems provide better drainage than a closed valley setup but require increased maintenance. The potential rust formation around metal flashing parts can cause severe leaks if left unchecked for long periods of time. To combat this weakness, regular maintenance and inspections are recommended to keep your home secure.

Which System Works Best For Houston Homes?

As previously mentioned, humidity levels rise significantly during warmer months in Houston, making waterproof protection paramount when deciding which valley style works best for your home.

With their continuous shingle seals, closed valley systems provide better protection against water infiltration than open valleys. Open systems lack a waterproof barrier along the top of the valley. As a result, closed valleys are generally more suitable for Houston homes — especially in areas prone to heavy rains or snowfall.

On the other hand, open valleys are viable if you need more natural ventilation between rafters. This can reduce temperatures within the attic space during hot summer months.

Whether you choose a closed or open valley system for your Houston home, ensure that your roof is properly flashed and sealed to ensure a fully waterproof roof with adequate ventilation. Professional installation of both open and closed valley systems can help you maintain the structural integrity of your home for years to come.

Houston Roofing & Construction Stands By Your Side

At Houston Roofing & Construction, our team of experienced RCAT-licensed professionals understands the nuances of open and closed-valley roof systems. We specialize in everything from expert installation and maintenance to total system replacements.

We’ll get the job done right the first time, so you don’t have to worry about further damage or costly repairs down the line. As GAF Master Elite Certified roofing contractors in Houston, TX, we offer customized solutions that not only meet but exceed industry standards.

Contact us today to get a free estimate or to learn more about our premium roofing services.

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