DIY Cedar Shake Roof Installation: A Complete Step-by-Step Guide to a Beautiful, Long-Lasting Roof

Installing a cedar shake roof yourself is a ambitious project that rewards the diligent homeowner with unmatched natural beauty and enduring performance. This guide walks through the entire process, from selecting the right materials to securing the final course of shingles, ensuring a weather-tight finish. While the task requires a significant time investment and physical effort, the satisfaction of completing a high-quality, time-honored roofing system is profound.

Understanding Cedar Shakes vs. Shingles

Before purchasing a single bundle, it is essential to distinguish between true cedar shakes and shingles, as the installation methods differ significantly. Cedar shakes are hand-split or sawed to create a thicker, more rustic profile with a rough, textured surface that provides excellent insulation and a dramatic aesthetic. Cedar shingles, on the other hand, are machine-sawn to a uniform thickness on both sides, resulting in a smoother, more refined appearance. This DIY guide primarily focuses on the installation of traditional cedar shakes, which require more robust underlayment and precise alignment due to their varying thickness.

Safety and Structural Preparation

Safety is non-negotiable when working at height, and a steep roof demands the utmost caution. Begin by ensuring the roof deck is structurally sound, free of rot or damage, and capable of supporting the weight of the cedar, underlayment, and fasteners. You must install sturdy scaffolding or use an extension ladder with a stable anchor point, supplemented by a harness attached to a secure roof anchor. Never rely solely on a standard ladder for an extended period, as the work involves constant climbing with heavy bundles of shakes.

• Inspect the roof framing for any signs of sagging or weakness.
• Use a harness certified for fall protection, attached to a fixed anchor point.
• Clear the work area of debris and secure tools with a hoist line.

Material and Tool Requirements

Successful installation hinges on having the correct tools and materials. Investing in quality equipment will save time and frustration, leading to a straighter, more professional finish. You will need a variety of specialized tools that go beyond a standard homeowner’s toolkit, particularly for cutting and fastening the dense cedar wood.

Climate and Ventilation Considerations

Cedar is a natural material that responds to moisture, making proper ventilation and an air gap critical to the roof's longevity. In climates with high humidity or significant rainfall, allowing air to circulate between the cedar and the roof deck prevents mold growth and wood rot. You must install "breathable" felt paper rather than standard tar paper and ensure that the eaves and ridge vents are functioning correctly to allow moist air to escape.

The actual installation begins with a solid substrate. Remove any old roofing down to the deck and inspect the sheathing for damage. Install a layer of undamaged plywood or oriented strand board (OSB) if the existing deck is compromised. Next, roll out the underlayment horizontally across the roof, securing it with cap nails. Pay special attention to overlapping the seams correctly—typically 2 to 4 inches—to direct water down the slope and prevent water intrusion at the joints.

The Installation Sequence and Techniques

With the deck prepared and underlayment in place, you can begin laying the shakes. Starting at the bottom edge of the roof, known as the eave, you will establish the correct exposure—the distance between the top of one course and the top of the course below it. This exposure is usually between 5 and 7 inches, but you must follow the specific recommendations provided by the shake manufacturer. Using a chalk line, snap horizontal guidelines across the entire roof to serve as your visual guide, ensuring a straight, level course.

When positioning the first course of shakes, align the edge of the shake with the edge of the roof, but remember to factor in the width of the drip edge flashing if you are using it. Nails should be placed in the "high" or "dead" spots of the shake— the natural raised grain— to allow for wood expansion. Avoid nailing too close to the edges or ends, as cedar is prone to splitting. As you progress upward, use a level to check that the course remains straight, and stagger the vertical seams of the shakes in a brick-like pattern to maximize water resistance.