Your roof can leak, buckle, tent, and sag. Did you know it can also shrink? As temperatures fluctuate and wind and rain take their toll, your roof’s waterproof membrane can contract. But what are the signs your roof is shrinking, and what should you do if it happens to you?
What Is Roof Shrinkage?
The name says it all. Roof shrinkage occurs when the protective membrane under your shingles contracts. A shrinking protective layer can lead to more significant problems and damage shingles and other roofing materials if you don’t catch it early. Shingles can crack, tear, or tent and metal flashing can shift and lose effectiveness.
What Causes Roof Shrinkage?
The membrane layer between your shingles and wooden decking protects your roof. It prevents leaks and rots, keeping your roof solid and stable. However, the protective membrane can shrink if the membrane is improperly installed–or takes a beating from the elements. As it contracts, the membrane pulls at your flashing, the metal strips that divert stormwater off your roof, causing damage and leaks. Improper installation and subpar membrane materials are two leading causes of shrinkage. For example, when you install an EPDM synthetic rubber membrane, your contractor should treat it to prevent UV damage. Weather conditions, including UV exposure and damage from wind and rain, can also cause your membrane to contract. Finally, poor roof design and inadequate ventilation can contribute to shrinkage. That’s one reason starting with a reputable, licensed roofing contractor is the way to go.
Do I Need A Roof Membrane?
When you and your roofer select a protective membrane, your roofer purchases the materials in rolls or squares for installation. Your membrane can be synthetic rubber, plastic, or asphalt. Your roofing contractor will guide you based on budget, weather conditions, and your roof’s exposure to the sun. If your roof has a steep slope, you may not need a membrane layer. However, for most flat and low-slope roofs, it’s a must. Options include:
- Synthetic rubber membranes like ethylene propylene diene terpolymer (EPDM) are a popular choice because they’re heat and fire-resistant. However, they must be treated for UV resistance and tend to shrink as they age.
- In flat commercial roofs, we often use thermoplastic membranes, including polyvinyl chloride (PVC) and thermoplastic olefin (TPO). They offer durability, heat resistance, and affordability.
- Modified bitumen membranes include variations made with rubber and plastic to increase strength and flexibility.
What Should I Do If I Suspect Roof Shrinkage?
If shrinkage may be behind leaks or damage to shingles, the first step is to schedule an inspection with a qualified contractor. Your roofer can determine the extent of the damage and recommend replacement or repair. If your shrinkage occurs because of improper installation, you want to correct past errors and do the job right. In some cases, your warranty may cover the cost.
How Can I Prevent Roof Shrinkage?
The first step in preventing roof shrinkage is a professional installation with a reputable contractor. Don’t be afraid to ask questions. Is your roofer licensed, bonded, and insured? What supplier do they use for the protective membrane layer? Another essential element in preventing roof shrinkage is protecting your roof with regular inspections and maintenance. Maintaining your roof instead of waiting for an emergency is a long-term money saver. Your roofing contractor should be available for routine inspections and maintenance. At DryHome Roofing and Siding, our team understands that regular maintenance and preventive measures keep your roof in great shape. If you suspect storm damage or wear and tear caused by aging, let’s schedule an inspection. It’s the best way to catch warning signs like shrinkage early and avoid costly repairs down the road.
