CSSB Trade Show & AGM 2026
October
14-15, 2026
Chicago, IL
Why Grading Matters When Buying Cedar Shingles
Press Release |
October 30, 2026
At the Cedar Shake & Shingle Bureau, we have been setting the benchmark for cedar quality since 1915, and few decisions affect a roofing project’s long-term performance more than understanding why grading matters when buying cedar shingles. Grade is a technical classification that determines the structural integrity, weathering behaviour, and service life of every shingle that goes on a roof. Purchasing without that knowledge is how projects fail ahead of schedule.
What the Grading System Actually Measures
Cedar shingle grades are not arbitrary rankings. Each grade reflects measurable characteristics evaluated at the time of manufacture, and those characteristics have direct consequences for how the material performs in the field.
The grading system assesses four primary factors:
- Grain orientation: Edge-grained (vertical grain) shingles resist cupping, warping, and moisture absorption far better than flat-grained material. Higher grades require edge grain throughout.
- Knot size and frequency: Knots interrupt grain continuity and create weak points where water infiltration and splitting are more likely to occur.
- Sapwood content: Heartwood contains the natural preservative oils that give cedar its durability. Sapwood does not. Premium grades limit or exclude sapwood entirely.
- Clear length: This is the defect-free portion of the shingle measured from the butt. Grade is largely determined by how much of the shingle is clear, because that is the exposed, weather-facing section once installed.
Each of these factors compounds the others. A shingle with flat grain, high sapwood content, and significant knots will weather differently, and far sooner, than a clear, edge-grained heartwood shingle, even if both come from the same species.
Grade Levels and What They Mean in Practice
No. 1 Grade
No. 1 cedar shingles are the standard for exposed roofing and sidewall applications where long-term performance is the expectation. They are edge-grained, 100% heartwood, and clear for the full length that will be exposed to weather. This is the grade we certify under the Certi-label® program for premium applications, and it represents what true craftsmanship demands from the material itself.
No. 2 Grade
No. 2 shingles allow for flat grain and limited sapwood, though they still carry a clear length sufficient for standard weather exposures. They are appropriate for secondary roofing applications or projects where budget constraints exist and exposure requirements are less demanding. Contractors who specify No. 2 for a primary roof slope in a high-moisture climate are accepting a meaningfully shorter service life.
No. 3 Grade
No. 3 is a utility grade. The clear length is reduced, and both flat grain and sapwood are present in greater proportions. This grade is appropriate for underlayment courses, starter courses, and applications where the material will not be exposed to direct weathering. Specifying No. 3 for exposed applications is a material error, not a cost-saving measure.
Find out how long a cedar roof lasts.
Why Certification Matters as Much as Grade
Knowing the grade designations is necessary. Knowing that the grade designation on a bundle is accurate is equally necessary.
This is where the Certi-label® certification program functions as a quality assurance mechanism rather than a marketing claim. Certified products have been graded against established standards by qualified inspectors, providing specifiers and contractors with confidence that what the label states reflects what is actually in the bundle. Without third-party certification, grade labelling is self-reported and unverified.
For trade professionals, this distinction matters at the specification stage. When a project calls for No. 1 cedar, the Certi-label® mark is the verification that the material meets that specification. Substituting uncertified product introduces liability that no installer should absorb.
The Cost Calculation That Gets Overlooked
Lower-grade shingles cost less per square at the point of purchase. The error is treating that as a straightforward savings.
The actual cost comparison involves more than the initial invoice. Service life is the first variable: a No. 1 cedar roof installed correctly will significantly outlast a No. 2 or No. 3 application on the same slope and climate exposure. Maintenance frequency is the second: lower grades are more prone to cupping, splitting, and uneven weathering, each of which accelerates deterioration and increases the intervals between required repairs. Re-roofing labour is the third and most consequential variable. When a roof fails early, the labour cost of replacement is not discounted. Only the material was cheaper the first time.
For any exposed roofing application where longevity is a stated goal, the arithmetic on grade selection resolves clearly toward investing in No. 1 certified material from the outset.
Specifying With Confidence
When we review grading standards with contractors and specifiers, the consistent finding is that grade-related failures are rarely the result of poor installation technique. They result from material that was graded wrong, specified wrong, or selected on price alone without accounting for the performance variables the grading system is designed to communicate.
Cedar is a premium material with a century-long track record when it is sourced correctly. The grading system exists to protect that track record, and the investments of everyone who builds with it.
To learn more about our Certi-label® certification standards or to connect with a certified manufacturer for your next project, reach out to us directly through the contact form on our website.
At the Cedar Shake & Shingle Bureau, we have been setting the benchmark for cedar quality since 1915, and few decisions affect a roofing project’s long-term performance more than understanding why grading matters when buying cedar shingles. Grade is a technical classification that determines the structural integrity, weathering behaviour, and service life of every shingle that goes on a roof. Purchasing without that knowledge is how projects fail ahead of schedule.
What the Grading System Actually Measures
Cedar shingle grades are not arbitrary rankings. Each grade reflects measurable characteristics evaluated at the time of manufacture, and those characteristics have direct consequences for how the material performs in the field.
The grading system assesses four primary factors:
- Grain orientation: Edge-grained (vertical grain) shingles resist cupping, warping, and moisture absorption far better than flat-grained material. Higher grades require edge grain throughout.
- Knot size and frequency: Knots interrupt grain continuity and create weak points where water infiltration and splitting are more likely to occur.
- Sapwood content: Heartwood contains the natural preservative oils that give cedar its durability. Sapwood does not. Premium grades limit or exclude sapwood entirely.
- Clear length: This is the defect-free portion of the shingle measured from the butt. Grade is largely determined by how much of the shingle is clear, because that is the exposed, weather-facing section once installed.
Each of these factors compounds the others. A shingle with flat grain, high sapwood content, and significant knots will weather differently, and far sooner, than a clear, edge-grained heartwood shingle, even if both come from the same species.
Grade Levels and What They Mean in Practice
No. 1 Grade
No. 1 cedar shingles are the standard for exposed roofing and sidewall applications where long-term performance is the expectation. They are edge-grained, 100% heartwood, and clear for the full length that will be exposed to weather. This is the grade we certify under the Certi-label® program for premium applications, and it represents what true craftsmanship demands from the material itself.
No. 2 Grade
No. 2 shingles allow for flat grain and limited sapwood, though they still carry a clear length sufficient for standard weather exposures. They are appropriate for secondary roofing applications or projects where budget constraints exist and exposure requirements are less demanding. Contractors who specify No. 2 for a primary roof slope in a high-moisture climate are accepting a meaningfully shorter service life.
No. 3 Grade
No. 3 is a utility grade. The clear length is reduced, and both flat grain and sapwood are present in greater proportions. This grade is appropriate for underlayment courses, starter courses, and applications where the material will not be exposed to direct weathering. Specifying No. 3 for exposed applications is a material error, not a cost-saving measure.
Find out how long a cedar roof lasts.
Why Certification Matters as Much as Grade
Knowing the grade designations is necessary. Knowing that the grade designation on a bundle is accurate is equally necessary.
This is where the Certi-label® certification program functions as a quality assurance mechanism rather than a marketing claim. Certified products have been graded against established standards by qualified inspectors, providing specifiers and contractors with confidence that what the label states reflects what is actually in the bundle. Without third-party certification, grade labelling is self-reported and unverified.
For trade professionals, this distinction matters at the specification stage. When a project calls for No. 1 cedar, the Certi-label® mark is the verification that the material meets that specification. Substituting uncertified product introduces liability that no installer should absorb.
The Cost Calculation That Gets Overlooked
Lower-grade shingles cost less per square at the point of purchase. The error is treating that as a straightforward savings.
The actual cost comparison involves more than the initial invoice. Service life is the first variable: a No. 1 cedar roof installed correctly will significantly outlast a No. 2 or No. 3 application on the same slope and climate exposure. Maintenance frequency is the second: lower grades are more prone to cupping, splitting, and uneven weathering, each of which accelerates deterioration and increases the intervals between required repairs. Re-roofing labour is the third and most consequential variable. When a roof fails early, the labour cost of replacement is not discounted. Only the material was cheaper the first time.
For any exposed roofing application where longevity is a stated goal, the arithmetic on grade selection resolves clearly toward investing in No. 1 certified material from the outset.
Specifying With Confidence
When we review grading standards with contractors and specifiers, the consistent finding is that grade-related failures are rarely the result of poor installation technique. They result from material that was graded wrong, specified wrong, or selected on price alone without accounting for the performance variables the grading system is designed to communicate.
Cedar is a premium material with a century-long track record when it is sourced correctly. The grading system exists to protect that track record, and the investments of everyone who builds with it.
To learn more about our Certi-label® certification standards or to connect with a certified manufacturer for your next project, reach out to us directly through the contact form on our website.
