Corrugated metal roofing panels are the foundation of a metal roof, but the accessories are what make it watertight and professional-looking. Missing even one component can lead to leaks, poor appearance, or premature failure. Here are the five essential accessories for any metal roofing project near Sacramento and Northern California.

1. Ridge Caps

Ridge caps seal the peak of a gable roof where two roof planes meet. Without a ridge cap, the open peak becomes a direct entry point for water, birds, and debris. Metal ridge caps are available in 10ft lengths and should match the color of your roofing panels. Install them with the correct roofing screws and sealant tape or closure strips for a watertight peak.

For the best appearance, use factory-cut ridge caps designed for corrugated panel profiles rather than improvised alternatives. The factory profile conforms to the panel corrugations, leaving smaller gaps and requiring less sealant.

2. Flashing

Flashing protects every transition point on a roof and building exterior — where panels meet walls, where panels turn corners, at rake edges, and at any penetration like a vent pipe or skylight. L-shaped flashing (also called L trim or drip edge) is the most common type and handles both inside and outside corners, eave drip edges, and wall-to-roof connections.

Color-matched 10ft L flashing in 2×2 or 2×4 profiles is available in the same 6 colors as the roofing panels. Using matched flashing gives the installation a cohesive, finished appearance rather than the mismatched look of standard unpainted aluminum flashing.

3. Roofing Screws with Sealing Washers

The screw is where water gets in if you use the wrong fastener. Roofing screws for corrugated metal panels must have a sealing washer — typically a rubber or EPDM gasket — that compresses against the panel face when the screw is driven. This creates a waterproof seal around the fastener hole.

Drive screws to the correct torque: tight enough to compress the washer slightly, but not so tight that you crush the washer or dimple the panel. On a 26 gauge corrugated panel, screws are typically installed at each valley (the low point of the corrugation profile) through the purlins or decking below. Follow the manufacturer’s recommended fastening pattern for your specific panel profile.

4. Closure Strips

Closure strips fill the open gaps between corrugated panels and flat surfaces at eaves, ridges, and wall connections. They prevent insects, birds, and wind-driven water from entering under the panels at these edges. Closure strips are typically made from foam rubber pre-formed to match the corrugated panel profile — both inside closures (fitting under the panel from below) and outside closures (fitting over the panel from above).

Do not skip closure strips on a permanent installation. The corrugation profile leaves open gaps at flat surfaces that are large enough for insects and small animals to enter, and they allow significant air and water infiltration in California wind and rain conditions.

5. Butyl Tape or Roofing Sealant

Butyl tape is applied along horizontal overlaps between panels and at flashing connections to create a continuous seal. It stays flexible over time, resists UV degradation, and bonds well to galvanized and painted steel. Apply butyl tape before overlapping panels at horizontal laps, and behind flashing legs that press against walls or panels.

For exposed joints and penetrations, use a compatible roofing sealant rated for metal and painted surfaces. Avoid standard caulk not rated for exterior metal use — it will crack and fail faster than purpose-designed roofing sealants.

Where to Get Metal Roofing Accessories Near Sacramento

Ridge caps, L flashing (inside corner and 2×2), roofing screws, and corrugated panels are available in Sacramento, Citrus Heights, Roseville, and Northern California. All accessories are available in 6 colors to match your panels. Call 916-940-5700 to check current stock and pricing for your project.