Masterpiece Roofing

Why metal roofs expand and contract

Metal Roof Noise | Why It Pops & What to Do

July 19, 20255 min read

The primary reason metal roofs make popping noises is due to thermal expansion and contraction. Metal, like all materials, expands when it heats up and contracts when it cools down. Metal, however, has a higher coefficient of thermal expansion compared to other common roofing materials such as asphalt shingles or wood.

This means that metal panels will expand and contract more significantly and at a faster rate in response to temperature fluctuations. When the sun hits a metal roof, it heats up rapidly and expands. As temperatures drop, especially at night or during a sudden cold snap, the metal cools and contracts. This movement, often occurring against fasteners or where panels meet, creates friction and tension that can release as an audible "pop," "click," or "creak."

Common sources of popping or creaking sounds

The sounds you hear from your metal roof can originate from several points:

  • Panel Movement: As the large metal panels expand and contract, they subtly slide against the clips or fasteners that secure them to the roof deck. This friction and subsequent release of tension is the most common cause of popping.

  • Fasteners: If fasteners (screws or clips) are overtightened or improperly installed, they can restrict the natural movement of the panels, leading to increased stress and louder pops as the metal tries to move.

  • Flashings and Trim: Metal flashings around chimneys, skylights, vents, or along the eaves and rake edges also expand and contract. These smaller metal components can rub against the main roof panels or the underlying structure, creating distinct sounds.

  • Underlying Decking: Even the wood sheathing (plywood or OSB) beneath your metal roof can contribute to noise. As it expands and contracts, it may shift slightly against the metal panels or its own fasteners.

  • Purlins/Substructure: If the metal roof is installed over purlins (horizontal framing members) rather than directly on a solid deck, the movement of the panels against these supports can sometimes generate noise.

  • Oil Canning (Pan Popping): In some cases, localized buckling or "oil canning" (visible waviness in the flat part of the panel) can occur during thermal movement, which may be accompanied by popping sounds as the panel flexes.

Is the noise harmful or just annoying?

In most cases, the occasional popping, ticking, or creaking sounds from a metal roof are normal and harmless. They are an inherent characteristic of the material's thermal movement and do not necessarily indicate a problem with the roof's integrity or performance. A properly installed metal roof is designed to accommodate this expansion and contraction without suffering damage.

However, there are situations where the noise could signal a potential issue:

  • Excessive Loudness or Frequency: If the sounds are unusually loud, constant, or significantly more frequent than typical, it might indicate that the panels are experiencing excessive stress, possibly due to improper installation where thermal movement is restricted.

  • Visible Damage: If the noises are accompanied by new visible signs of damage such as loose fasteners, bent or warped panels, visible oil canning that wasn't there before, or signs of leaks (water stains in the attic or interior), then it's a concern.

  • Noise from a Newly Installed Roof: While some initial settling noises are normal, persistent and excessive popping on a new roof could indicate an installation error.

If you have any doubts or observe any of these warning signs, it's always wise to consult a professional roofer for an inspection.

How to minimize roof noise

While eliminating all noise from thermal expansion is unlikely, especially in climates with significant temperature swings, there are several ways to minimize it, particularly during installation:

  • Proper Installation: This is paramount. A professional metal roofing contractor like Masterpiece Roofing understands the importance of:

    • Allowing for Movement: Using fastening systems (like floating clips for standing seam roofs) that allow the panels to expand and contract freely.

    • Correct Fastener Spacing: Ensuring fasteners are not overtightened or improperly spaced, which can restrict movement.

    • Panel Length: Designing the roof with appropriate panel lengths to manage thermal movement effectively.

  • Quality Underlayment: Installing a high-quality underlayment beneath the metal panels provides a smoother surface for the metal to slide on and can act as a sound dampener.

  • Proper Insulation: Adding adequate attic insulation, such as rigid foam boards or spray foam, can serve as a sound barrier, absorbing vibrations and reducing the transmission of noise into your living space. Good insulation also helps stabilize the temperature of the roof deck, reducing extreme temperature fluctuations.

  • Lighter Colors: Choosing lighter-colored metal roofing panels can help reduce heat absorption, thus minimizing the degree of thermal expansion and contraction.

  • Roof Design: For new constructions, specific roof designs that account for thermal movement can help.

  • Regular Maintenance: Keep your roof clean of debris and ensure drains are clear. Regular inspections can identify loose fasteners or minor issues before they become sources of increased noise.

When to call a roofer for inspection

While many metal roof noises are benign, it's crucial to know when to call a professional for an inspection to ensure your roof's long-term integrity:

  • Persistent or Worsening Noise: If the popping or creaking becomes significantly louder, more frequent, or constant, rather than just occurring during temperature changes.

  • Visible Roof Damage: Any signs of panel warping, buckling, loose or pulled-out fasteners, or damaged flashing.

  • Leaks or Water Stains: The most critical sign. If you notice any water stains on your ceilings or walls, or signs of moisture in the attic, it could indicate a compromised seal.

  • Recent Storm Damage: If the noises began after a severe storm with high winds or heavy hail, there might be unseen damage.

  • Age of the Roof: If your metal roof is very old and the noises are a new development, it might be a sign of material fatigue or aging components.

Masterpiece Roofing has the expertise to thoroughly inspect your metal roof, diagnose the precise cause of any unusual noises, and recommend the best course of action. We can assess the installation quality, check for structural issues, and perform any necessary repairs to ensure your metal roof continues to provide durable, worry-free protection for your home.

Back to Blog

Office: 1248 Highland St, Holliston, 01746 MA

(508) 882-6080

Email: office@buttonmasterpieceroof.com

Site: www.masterpieceroof.com

Assistance Hours

Mon – Fri 8:00am – 4:00pm