Class 3 vs Class 4 Roofing Shingles in Alberta

A Brief Homeowner Guide

In Alberta, where hailstorms are frequent and often severe, impact-resistant roofing materials are an important consideration. One of the most common questions homeowners ask is:

“What’s the difference between Class 3 and Class 4 shingles?”

The distinction primarily relates to impact resistance, which affects durability, lifespan, and insurance considerations.

Understanding Impact Ratings (UL 2218 Standard)

Shingle impact ratings are based on the UL 2218 test, which evaluates how well roofing materials withstand simulated hail impact.

Class 1 → Lowest resistance

Class 4 → Highest resistance

Both Class 3 and Class 4 shingles are designed for hail-prone regions, but they perform differently.

Class 3 Shingles

Impact Resistance: Moderate–High

Class 3 shingles can withstand impact from a steel ball dropped from a specified height without cracking.

Key Characteristics

✅ Better resistance than standard shingles
✅ Suitable for moderate hail exposure
✅ Typically lower cost than Class 4
✅ May reduce minor damage risk

Limitations

⚠️ Less protection during severe hailstorms
⚠️ Higher probability of granule loss or bruising

Class 4 Shingles

Impact Resistance: Highest Available

Class 4 shingles undergo more demanding impact testing and are engineered to resist cracking under stronger impacts.

Key Characteristics

✅ Maximum hail resistance
✅ Best suited for Alberta’s climate
✅ Reduced risk of functional damage
✅ Longer expected service life in hail zones

Additional Benefits

✔ Often favored by insurance providers
✔ Potential premium discounts (varies by insurer)
✔ Lower long-term repair frequency

Practical Differences for Homeowners
Factor Class 3 Class 4
Impact Resistance High Very High
Hail Protection Good Excellent
Cost Lower Higher
Damage Probability Moderate Lower
Insurance Incentives Possible More Common
When Class 4 Makes Sense in Alberta

Class 4 shingles are generally recommended when:

✔ Property is in a hail-prone area
✔ Long-term durability is a priority
✔ Insurance incentives are relevant
✔ Reducing claim frequency matters

Class 3 shingles may be reasonable when:

✔ Budget constraints dominate
✔ Hail exposure risk is lower
✔ Shorter-term ownership planned

Important Clarification

👉 Impact rating ≠ hail-proof

Even Class 4 shingles can sustain cosmetic effects under extreme conditions. The rating primarily reduces functional damage risk, not eliminates it.

Bottom Line

Class 3 → Cost-effective protection

Class 4 → Maximum durability & risk reduction

In Alberta’s environment, Class 4 shingles are widely considered the safer long-term investment, particularly for homeowners concerned about repeated hail events.