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Quality North American Natural Slate Roof Shingles by North Country Slate
Introduction
With a commitment to providing the best quality and most beautiful natural roofing slate shingles available anywhere in the world, the choice of a North Country Slate roof for your building makes the statement that only the best is good enough. Along with this quality product, comes our well recognized technical support, design advice, industry knowledge, transportation services and dedication to maintaining extensive inventory.
What Is Natural Roofing Slate?
Natural roofing slate is a premium, long-lasting roofing material made from fine-grained stone that is split into thin tiles and installed in overlapping courses to provide superior weather resistance, durability, and architectural appeal for a century.
Reviews
Our Reputation is Only Measured by Our Clients Success
"I have never had anything except a 5 Star Experience when working with North Country Slate."
"I have dealt with many quarries over my 30 years, as well as the 2 generations before me. I can't say enough about the quality and consistency of the slate from North Country."
"We have used North Country black on a large number of occasions, and we’ve found it to be an excellent quality slate it is very “workable”."
Natural Slate Roof Shingles and Specialty Roofing Products
North American-made Natural Slate & Terra Cotta Roof Shingles
The Slate Standard: A 5-Point Quality & Specification Checklist
Choosing slate for a roof is about more than appearance. The material, specifications, installation details, and installer experience all play a direct role in how the roof performs over time.
At North Country Slate, we believe every project should begin with a clear standard. This five-point checklist gives homeowners, architects, and contractors a practical way to evaluate natural roofing slate before installation begins.
North Country Slate roofing products meet or exceed the Standard Specification for Roofing Slate under ASTM C 406-06. That includes testing under ASTM C 120 for flexure, ASTM C 121 for water absorption, and ASTM C 217 for weather resistance.
For material integrity, high-quality slate should meet several key benchmarks:
- ASTM S1 rating for the highest grade of roofing slate performance
- Ring test performance where a sound slate produces a clear, sharp, high-pitched ring when tapped, while a dull sound can point to softness, hidden defects, or delamination
- Uniformity, with slate that lies flat and maintains consistent thickness without bowing or twisting, ensuring accurate dimensional tolerances
- Material warranty, covering delamination or substantial deterioration of the body of the slate to the original purchaser for 75 years
Natural roofing slate is also graded by expected service life:
| Grade | Expected Service Life |
|---|---|
| Grade S1 | Over 75 years |
| Grade S2 | 40 to 75 years |
| Grade S3 | 20 to 40 years |
Physical requirements also matter when comparing slate grades:
| Classification | Breaking Load, Min. Pound-Force | Absorption, Max. Percentage | Depth of Softening, Max. Inches |
|---|---|---|---|
| Grade S1 | 575 lbf. | 0.25 | 0.002 |
| Grade S2 | 575 lbf. | 0.36 | 0.008 |
| Grade S3 | 575 lbf. | 0.45 | 0.014 |
Slate color affects more than curb appeal. It also shapes the character of the roof and the overall architectural look of the property. Depending on the project, slate can be selected in a single color, a blend of colors, or arranged in decorative patterns.
When reviewing options, it is also important to understand natural weathering characteristics. Some slate is considered unfading, meaning the colour remains consistent over time and is least likely to change. Other slate is semi-weathering, which means the surface tone gradually changes as the roof ages. Both can produce beautiful results, but the expected appearance should be part of the specification from the start.
Correct layout begins with the relationship between slate length, headlap, and exposure. A simple formula helps define the visible portion of each slate:
Slate Length minus Headlap, divided by 2 = Exposure
For example:
18” Length – 3” Headlap / 2 = 7.5” Exposure
Headlap is critical to ensure your roof stays watertight. It determines how much one slate overlaps the slate two courses below it, helping protect the roof system against water penetration. Exposure must always be calculated with the correct headlap in mind.
Roof pitch also influences these specifications. As roof pitch changes, layout requirements may need to change with it to maintain weatherproof and long-term performance. This is one of the reasons slate roof planning should always be handled with careful attention to the roof’s slope, the selected slate size, and the intended exposure.
Slate roof weight should always be reviewed early in the planning process. Traditional slate installation weights vary depending on the thickness of the slate, while alternate lightweight slate roofing system options can reduce the overall load on the structure.
Since weight affects structural planning, material selection, and installation details, it should be clearly identified in the roof specification. A weight-per-square chart can help compare traditional slate thicknesses with lightweight slate roofing and guide better decisions before installation begins.
Traditional Slate Installation
| Thickness (inches) | Approx. Weight per Square (3" Headlap) (lbs) | Estimated Lifespan (Years) |
|---|---|---|
| 3/16" | 700 | 75+ |
| 3/16" - 1/4" | 820 | 75+ |
| 1/4" | 935 | 75+ |
| 1/4"-3/8" | 1170 | 75+ |
| 3/8" | 1405 | 75+ |
| 3/8"-1/2" | 1640 | 75+ |
| 1/2" | 1870 | 75+ |
| 1/2"-5/8" | 2105 | 75+ |
| 5/8"-3/4" | 2575 | 75+ |
| 3/4"-1" | 3275 | 75+ |
Lightweight Slate Installation
| Thickness (inches) | Approx. Weight per Square (4" Overlap) (lbs) | Estimated Lifespan (Years) |
|---|---|---|
| 1/4"-3/8" | 600 | 75+ |
| 3/8"-1/2" | 900 | 75+ |
Even the best slate can underperform if it is installed incorrectly. Natural slate roofing requires experience, technical knowledge, and attention to specification details.
When evaluating an installer, look for:
- Contractor affiliations or recognition through respected industry organizations such as the National Slate Association (NSA) and Slate Roofing Contractors Association (SRCA)
- Installer’s warranty coverage
- Proven natural roofing slate experience
- A minimum of four project references for comparable slate roofing work
A qualified slate roofer should understand material grading, layout requirements, fastening practices, flashing integration, and installation methods specific to natural slate. That level of experience helps protect the investment and supports the long service life slate is known for.
Projects
Natural Roofing Slate Design Support Services
North Country Slate offers full-spectrum support from design through installation. We collaborate with homeowners, architects, and builders to ensure every natural slate roof shingles project aligns with structural needs, visual goals, and heritage requirements. Our team provides layout planning, headlap guidance, and slate size selection tailored to each property.
We also assist in choosing colors, thicknesses, and accessories that complement your design while maintaining long-term performance. During supply, we coordinate timely delivery from our inventory, including slate roof tiles and specialty accessories. On the installation side, we provide technical documents, job-site coordination, and installer referrals as needed, making the entire process as seamless as the slate itself.
We Look After Every Conceivable Detail
Design Support
Bring Your Vision to Life
Learn about our Lightweight Slate System
Homeowners, architects, and builders are welcome to contact North Country Slate for expert advice on lightweight slate roofing options. Our team can assist with product selection, design recommendations, pricing details, and installation planning.
Ready to get started? Call us at 866-703-9651 to speak with a specialist or contact us here to request a quote today.
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FAQs
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Is it possible to add snow guards to an existing slate roof?
Yes, there are retrofit snow guard solutions made for installation on roofs after they are installed.
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Is there a guideline for maintaining snow guards?
Similar to your slate roof, it is advisable to schedule an annual inspection to examine the snow guards for any damage or issues, particularly after experiencing significant snowfall and ice accumulation during the winter season.
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What are snow guards made of?
Snow guards come in aluminum, zinc, copper, lead-coated copper, brass and steel. Commonly used pad style snow guards are also available in a variety of colors.
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What is the difference between snow guards and snow rail system?
Snow guards are individual pieces which are distributed on the roof. Usually beginning up from the eaves and moving upward. The positioning will differ based on the slope of the roof and the weight of the snow. They may feature a classic pad shape or decorative patterns like flowers, birds and stars.
A snow rail (pipe-style) retention system serves as a robust barrier and more frequently found on commercial properties. These systems consist of various components: pipes, end caps and collars, couplings, and a base plate that replaces a slate shingle. These bar rail systems may consist of one, two or even three railings to prevent snow from avalanching off a roof.
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What is the function of a snow guard?
Snow guards are placed at strategic locations on a slate roof to manage the way snow is held in place to prevent sudden snow slides. Snow retention devices protect your gutters, landscaping and the safety of pedestrians. If you reside in a region that experiences snowfall each winter and your roof has a pitch steeper than 8:12, you might want to think about installing a snow retention system.
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