If you have a roofing problem, you already know just how challenging it can be. Not only does it damage the roof, but it can also create health and safety problems for your home. Common roofing problems are more evident than others, such as leaking roof valleys.
Leaks from roof valleys are one of the most common building problems, which is why we’ve put together a list of the most common causes of valley leaks and what you can do to fix them. Valley leaks can cause significant damage, not only to your home’s interior but also to your roof structure. A comprehensive repair will keep your home looking great and save on costly repairs down the road.
Common Problems with Roof Valleys
1. Underlayment
Leaks in roof valleys are often due to underlayment issues. The type of underlayment, its size, and the installation method all affect the lifespan of your valley. Underlayment can last as long as 25 years when the underlayment is installed correctly. However, improper installation or low-quality materials can cause problems within just a few years.
For instance, inexperienced roofers or DIYers often use roll roofing as the valley underlayment on asphalt shingle roofs. Though the product is only rated for a maximum 10-year life span, shingles can last for 25 years depending on how old the roof is and what type of material it was made from. While roll roofing can be used on many different roofs, it is not recommended for asphalt shingle roofs.
The better option for valley underlayment is to use galvanized steel or aluminum flashing, which provides a more durable layer. Always use 26-gauge or thicker flashing.
2. Thermal Expansion
Thermal expansion is another major issue. The valley underlayment will expand in warm weather and may wrinkle as a result. If you install metal valley underlayment, the wrinkles can cause holes, cracks, or tears. The wrinkles themselves can become large enough to redirect the water flow beneath the roofing material.
Valley underlayment should be installed in small sections to avoid thermal expansion damage. Make each piece two to three feet wide and no more than eight to ten feet long. Larger underlayment pieces will expand more than smaller ones, making them more likely to wrinkle or buckle.
3. Cross Wash
Cross wash is a problem that affects the valleys of a roof — it happens when water flows up one side of the valley instead of down. Although cross wash doesn’t damage roofs, it can cause leaks and roofing problems over time.
There are a few potential fixes involved here: first, ensure that the roofing material is fastened adequately along the valley’s edges. When in confusion, run a bead of sealant where the roofing material meets the valley underlayment to prevent cross wash leaks. Second, look for damage to the underside of your shingles. If there is any curl or buckling, replace them ASAP to avoid further water damage.
4. Snow On Standing Seams
While standing-seam roofs are more durable and long-lasting than conventional roofs, they can still be damaged by snow and ice storms. Since snow always flows down the valley in a standing seam roof, large chunks of snow can snag on the seams and bend them. This can weaken the overall structure of the roof and cause leaks.
If you want to avoid costly repairs in future winters, then you must take the time to purchase and install snow guards on your roof. Snow guards are the easiest way to prevent snow from working its way into the gaps between your roof’s shingle, which can eventually lead to problems like ice dams, leaks, and even mold growth on your ceilings.
If you’re experiencing a leak in one or more of your roof valleys, there’s a good chance that it’s preventable. These common problems can be avoided with careful, expert installation of flashing and underlayment, followed by applying sealants and snow guards. In many cases, you will avoid a significant leak altogether. You can always call our roofers at All Around Roofing, Siding & Gutters, and we will help you determine the extent of damage and how we can fix that.
