What is a Roof Valley and What is Its Purpose?

roof valley

If you’ve ever had to discuss your roof with a roofing contractor you’ve probably noticed that we speak a lot of roofing jargon. One term that often floors customers is ‘roof valley’ so we thought we’d use this article to shed some light on the subject and keep you informed.

It may seem odd to learn that you have a valley on your roof. It’s a term for the place where two roof surfaces meet together and it’s also one of the most common places for a roof to leak. These joins or roof valleys are typically covered with non-permeable materials such as roof rolls or metal sheets to keep out the moisture.

The definition of a roof valley

The majority of a roof is made up of a large flat expanse that’s normally covered with non-permeable materials such as slate or metal titles or asphalt shingles that serves to protect both the roof structure and the interior of the property. When two different roof surfaces come together it creates a valley. This valley or channel is intended to allow moisture to run off the roof.

Why flashing in valleys is so important

If your roofer states that there is a need to put flashings into a roof valley it’s because he is concerned that moisture could enter between the joins. Flashing is used to create an impermeable seal in the channel.

A build-up of leaves and debris in the channel is the reason that often roof valleys deteriorate faster than any other sections of the roof. Simply put, if a roof valley is clogged, the water is unable to run off. The accumulation of debris causes the flashing to weaken and corrode.

If your roof is leaking, a roofing contractor will often inspect the roof and find that the source of the problem is a leaking roof valley.

The Roofman offers a FREE roof inspection and will present you with a detailed report and a no-obligation quote for any repairs that need doing. Even if you don’t have a roof leak, it’s still recommended to inspect your roof on a regular basis as problems spotted early are easier and cheaper to repair. If you need assistance with your roof give the Roofman a call on 0410 452 234.