Why Shingles Cup and Crack, and How to Stop It

If you've noticed your cedar roof developing a curled, weathered appearance, you're witnessing a predictable pattern of degradation. Understanding why cedar shingles cup and crack is the first step toward protecting your investment.

Why Do Cedar Shakes Crack?

Cedar shakes are highly sensitive to weather changes. Over the years, a cedar roof faces constant wear from these main elements:

UV Exposure

Ultraviolet (UV) rays systematically break down the wood's cellular structure at the surface, making shakes increasingly brittle. This UV damage to cedar roof surfaces creates weakness that compounds the physical stress from wet-dry cycling. Eventually, the combination produces cracking and splitting that compromise your roof's protective function.

Biological Growth

Understanding why your wood shingles curl requires recognizing how these forces work together. Organic debris traps moisture on your roof, creating conditions that contribute to fungal growth and deterioration.

Once established, biological growth accelerates deterioration and makes it essential to prevent wood rot on the roof through professional intervention, such as expert maintenance from Cedar Roof Coatings.

Wet-Dry Cycles

Wood naturally swells when wet and shrinks when dry. This becomes problematic when shingles experience uneven moisture exposure. Cedar shakes absorb water during rain and swell uniformly. However, the top surface dries rapidly under direct sunlight while the underside remains wet and expanded. This differential creates physical distortion across the wood, resulting in cedar shingle cupping. Repeated wetting and drying induce stresses in the wood that eventually lead to cracks, cupping and warping.

In Fairfield County towns like Greenwich, Darien, Westport, and New Canaan, heavy coastal moisture combines with distinct seasonal changes to intensify this cycle. The effects of moisture on cedar become particularly pronounced during humid summers and wet winters.

The Cedar Wash and TWP 200 Treatment Process

Cedar Roof Coatings' professional process helps address these environmental stresses. Our two-step approach includes:

• Cedar Wash application: It removes damaging biological growth without harming wood fibers using an eco-friendly hydrogen peroxide formula.

• TWP 200 Series treatment: This treatment provides deep-penetrating protection that preserves the roof and protects it from moisture and moss growth.

So, how does TWP 200 work to protect your investment? This oil-based preservative helps repel excess moisture while reducing the risk of cupping. Treatments containing UV inhibitors help slow weathering. TWP 200 utilizes these UV inhibitors to help slow UV-related weathering and minimize cracking, making it the best option for treating cedar roofs.

Protect Your Fairfield County Home Today

Proactive, professional maintenance remains a reliable way to deter natural degradation. Cedar Roof Coatings is your local expert equipped to handle the weather challenges of Greenwich, New Canaan, Darien, and Westport. 

We provide cedar roof maintenance services to protect your home and keep it looking its best. Contact us today for a professional cedar roof inspection and secure your roof with our specialized cleaning and coating process.