Why Interlocking Metal Shingles Are Better Than Standing Seam (And Why They Don’t Oil-Can)
Metal roofing continues to grow across Ontario, and two roofing systems dominate homeowner discussions: standing seam panels and interlocking metal shingles.
Although standing seam is popular, many homeowners are surprised to learn that it has one unavoidable issue:
Standing seam panels almost always oil-can — but interlocking metal shingles do not.
In this guide, ROOFNOW™ breaks down why interlocking shingles are the superior choice for appearance, winter performance, and long-term durability.
Table of Contents
- What Is Oil Canning?
- Why Standing Seam Roofs Oil-Can
- Why Interlocking Metal Shingles Don’t Oil-Can
- Performance Benefits vs. Standing Seam
- Winter Performance in Ontario
1. What Is Oil Canning?
Oil canning is the visible waviness or rippling that appears on smooth metal roofing panels.
It does not affect the structure, but it ruins the appearance of the roof. Homeowners notice it most in the sun, where the ripples become obvious across the panels.
Standing seam metal roofs are the most prone to oil canning.
2. Why Standing Seam Roofs Oil-Can
Standing seam panels are long sheets of metal — often 20 to 30 feet in a single stretch. Because the panels are so large, they expand and contract dramatically with temperature changes.
This movement causes stress, which results in visible distortion:
- Thermal expansion forces the panel to deform
- Sunlight heat exaggerates surface waviness
- Wide flat pans show imperfections more clearly
- Roof deck irregularities transfer through the panel
No matter how perfectly a standing seam roof is installed, oil canning is considered normal and expected.
This is why many homeowners prefer a system that stays perfectly flat.
3. Why Interlocking Metal Shingles Do NOT Oil-Can
Interlocking metal shingles use smaller, structured panels instead of broad flat sheets. This completely eliminates the stress that causes oil canning.
Key reasons shingles stay perfectly flat:
- Small panel size = zero warping
- Four-way interlocking edges stabilize each piece
- Embossed patterns hide microscopic imperfections
- High-strength G90 steel resists distortion
Result: A permanently flat, premium appearance — no ripples, no waves, no distortion.
This is why ROOFNOW™ installs interlocking shingles for homeowners who care about appearance as much as performance.
4. Performance Benefits vs. Standing Seam
Interlocking metal shingles outperform standing seam in several key areas:
- Better aesthetics (zero oil canning)
- Superior stability due to the interlock system
- Easier repairs if a single panel is damaged
- Quieter during rain/hail than smooth panels
- More impact-resistant due to textured profiles
Standing seam is still a good system — but appearance issues are built into its engineering.
5. Winter Performance in Ontario
Ontario’s extreme winters highlight the advantages of interlocking shingles:
- Snow slides evenly without large sheets dropping at once
- Panels resist uplift during freeze–thaw windstorms
- No thermal shock distortion (standing seam expands fast)
- Excellent ice-dam prevention with proper underlayment
Your roof stays flat. Your roof stays beautiful. Your roof stays strong — with no oil canning ever.
Need Roofing Help? Contact ROOFNOW™
- Phone: 1-833-901-1649
- Main Site: ROOFNOW.ca
- Knowledge Hub: New.ROOFNOW.ca
Learn everything about roofing at New.ROOFNOW.ca, then get your free metal roofing quote at ROOFNOW.ca.
🏠 ROOF SMART. ROOF ONCE. ROOFNOW™.