The 5/16” thickness sets this fiber cement shake apart from standard 1/4” products. That extra sixteenth of an inch provides enhanced rigidity and impact resistance — measurable benefits when hail season hits Montana valleys. With Class A non-combustible rating and ASTM E84 scores of Flame Spread 0, Smoke Developed 5, it meets the strictest wildfire zone requirements. CalFire WUI Listed under certification numbers 8170-2180:0501 & 0502 makes it suitable for Montana’s increasing Wildland-Urban Interface construction.
Performance Specifications That Matter
At 85 lb/ft³ density, this shake delivers substance contractors can feel during installation. The material resists freeze-thaw cycles — critical for Montana’s 100+ annual temperature swings. Rot-proof and moisture-resistant properties mean it won’t swell, rot, or buckle under spring snowmelt conditions.
| Specification | Value | Source |
|---|---|---|
| Thickness | 5/16 inch | Manufacturer |
| Dimensions | 16” × 48” (4 feet) | Manufacturer |
| Exposure | 7 inches | Manufacturer |
| Weight per Panel | 13.1 - 16.0 lbs | Manufacturer |
| Density | 85 lb/ft³ | Manufacturer |
| Coverage per Panel | 2 sq ft | Manufacturer |
The staggered edge profile creates deeper shadow lines than straight-edge alternatives. Compared to typical James Hardie Shingle at 1/4” thickness, the additional material provides both visual depth and structural benefits. Allura’s staggered edge creates deeper shadow lines and more realistic grain — contractors notice the difference on finished walls.
Installation Requirements for Montana Conditions
Installation demands corrosion-resistant siding nails (hot-dip galvanized or stainless) spaced 12” on center at studs. No shortcuts here. Maintain 6” clearance from soil/ground and 2” clearance from hard surfaces like roofing, decking, or sidewalks. These clearances prevent moisture wicking and freeze damage.
Carbide-tipped saw blades or fiber cement shears are required for cutting. Standard wood blades won’t cut it. All cut edges and joints need sealing with high-quality paintable caulk — the manufacturer specifically mentions OSI QUAD Max as a compatible option.
Panels install from the bottom up with 7-inch exposure, overlapping according to the staggered profile. The staggered design requires attention during layout to maintain proper alignment.
Durability Beyond the Warranty
The product carries a 30-year limited transferable product warranty. Factory-applied coatings come with either 15-year or 30-year limited warranties depending on whether you choose Allura Spectrum or Sherwin-Williams finishes. Warranty coverage requires installation per manufacturer’s guidelines, including specific fastening and clearance requirements.
Factory-applied coatings are designed for long-term color retention against Montana’s high-altitude UV exposure. Contractors report the material can be heavy and requires careful handling to avoid breakage — a trade-off for the enhanced thickness.
Frequently Asked Questions
What makes the 5/16” thickness worth the extra weight?
The thicker panel provides enhanced rigidity and durability. In practical terms, it resists impact better during hailstorms and handles jobsite abuse better than thinner alternatives. The weight difference shows up during installation but pays off in long-term performance.
How does this compare to natural cedar shakes in fire zones?
Unlike combustible wood, this fiber cement carries a non-combustible Class A rating. It won’t rot, split, or attract insects like real cedar. The product is specifically designed for high-risk fire zones (WUI - Wildland-Urban Interface).
What specialized tools are absolutely necessary?
Installation requires specialized tools including carbide blades and fiber cement shears. Proper installation including clearing, fastening, and sealing is critical to prevent moisture issues or cracking. Don’t attempt installation with standard wood-cutting equipment.
Can this handle Montana’s freeze-thaw cycles?
Yes, the material is specifically rated as resistant to freeze-thaw cycles. Its moisture-resistant properties mean it won’t swell, rot, or buckle when exposed to repeated temperature cycling and moisture.
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