How to Use Furring Strips for Metal Roofing: 1 Minute to Installing a Metal Roof with Furring Strips

Furring strips are a crucial component when installing metal roofing, providing a stable base, improving ventilation, and preventing condensation. These narrow boards or metal strips are fastened perpendicular to the roof rafters, allowing you to attach the metal panels securely. Here’s a step-by-step guide on how to use furring strips for metal roofing, ensuring a durable and energy-efficient roof system.

1. Gather Your Materials: You’ll need treated lumber or metal furring strips (typically 1x2 or 1x3), a drill, roofing screws, a measuring tape, chalk line, level, and safety gear. Treated wood is ideal because it resists moisture and pests, while metal furring strips are favored for their longevity and fire resistance.

2. Prepare the Roof Surface: Ensure your roof sheathing or rafters are solid and free of rot. Lay down a waterproof underlayment—this acts as an extra barrier against moisture. Mark the layout for your furring strips using the chalk line, spacing them 24 inches apart for most metal roofing panels (always check manufacturer recommendations for specific requirements).

3. Install the Furring Strips: Start at the eaves and work up to the ridge, running strips horizontally across the rafters. Use a level to keep them perfectly straight, since uneven strips can cause installation issues or rattling in windy conditions. Secure each strip using corrosion-resistant screws, anchoring them into the rafters beneath for a solid hold.

4. Add Insulation or Venting If Needed: The gap created by furring strips improves airflow and can be used to add rigid foam insulation, enhancing energy efficiency. Proper ventilation also prevents condensation buildup, which can otherwise lead to mold growth or rusting.

5. Attach the Metal Roofing Panels: Once all furring strips are in place, align your metal roofing panels over the strips per the manufacturer instructions. Fasten the panels through the raised sections into the center of each furring strip, being careful not to overtighten, as this could deform the panels or compress any seals.

As a professional interior designer, I always approach structural changes—like adding furring strips—not just for functionality, but also for optimizing comfort, energy efficiency, and even aesthetics. Ensuring your roof assembly is well-planned creates a more comfortable living environment below and increases the longevity of your metal roof. In this same spirit, effective planning tools such as a 3D floor planner can be invaluable when visualizing how your choices above will impact your interiors below, especially when considering things like ceiling heights or adding insulation layers.

Tips 1:

Double-check local building codes before you start; spacing and materials may have regulated standards in your area. Using furring strips over an old shingle roof can also work, but inspect the old surface for damage and consider the added weight.

FAQ

Q: What type of wood should I use for furring strips?

A: Pressure-treated wood is preferred due to its resistance to moisture and insects, essential for long-term durability under metal roofing.

Q: How far apart should furring strips be placed for metal roofing?

A: Most manufacturers recommend spacing strips 24 inches apart, but always verify with your chosen panel’s instructions for precise spacing.

Q: Can I use metal furring strips instead of wood?

A: Yes, metal furring strips offer fire resistance and longevity. Choose based on your local climate, code, and budget considerations.

Q: Do furring strips help with roof ventilation?

A: Absolutely. The air gap beneath the metal panels helps prevent condensation and improves thermal performance, reducing heat transfer and moisture issues.

Q: Are furring strips necessary for metal over existing shingles?

A: While you can lay metal roofing over existing shingles, furring strips are recommended to create an even surface, ensure adequate ventilation, and extend the life of your new roof.