what screws to use for composite decking

3 min read 26-12-2024

what screws to use for composite decking

Choosing the right screws is crucial for a long-lasting, beautiful composite deck. Using the wrong screws can lead to unsightly gaps, damaged boards, and an overall shorter lifespan for your deck. This comprehensive guide will help you navigate the world of composite decking screws and choose the perfect fasteners for your project.

Understanding Composite Decking Materials

Before diving into screw types, it's important to understand the material you're working with. Composite decking is a blend of wood fibers and plastic, creating a durable, low-maintenance alternative to traditional wood. However, this composite material requires specific screws designed to avoid damage. Standard wood screws are often too aggressive and can strip the composite material.

Types of Screws for Composite Decking

Several screw types excel when working with composite decking. Each offers unique advantages and disadvantages:

1. Composite Decking Screws

These are specifically engineered for composite decking materials. They typically feature:

Coated Shanks: These prevent the screws from damaging the composite during installation. Common coatings include zinc, stainless steel, or specialized polymer coatings.
Sharp, Self-Tapping Points: These allow for easier installation without pre-drilling in most cases.
Self-Countersinking Heads: These create a flush surface, minimizing the risk of splintering or damage.
Various Head Styles: You'll find options like pan heads, bugle heads, and flat heads to match your decking's aesthetic.

Pros: Designed for the job, ensuring optimal performance and longevity.

Cons: Can be slightly more expensive than other options.

2. Stainless Steel Screws

High-quality stainless steel screws offer excellent corrosion resistance, making them ideal for outdoor applications. However, ensure they're designed for composite materials—not all stainless steel screws are created equal. Look for screws with a similar shank design to dedicated composite decking screws.

Pros: Durable and resistant to rust and corrosion.

Cons: Can be more expensive than other options and may require pre-drilling depending on the hardness of the composite material.

3. Coated Wood Screws (Use with Caution)

Some coated wood screws might work, but it's crucial to choose ones with a very fine thread and a coating designed to minimize damage to the composite material. Always test in an inconspicuous area first.

Pros: More readily available and often cheaper.

Cons: High risk of stripping the composite if not chosen carefully. Not recommended as a primary option.

Choosing the Right Screw Length

Screw length is critical. Too short, and the screw won't provide sufficient holding power. Too long, and it might pierce the decking board below. A good rule of thumb is to select a screw length that's approximately 1 ½ to 2 times the thickness of the decking board.

Essential Tips for Installation

Pre-drilling: While many composite screws are self-tapping, pre-drilling a pilot hole with a slightly smaller drill bit can prevent splitting, especially with thicker decking boards or harder composite materials. This is especially helpful in dense materials.
Using a Driver: Use a quality drill driver with the appropriate bit to prevent cam-out (the screw slipping out of the driver). A magnetic bit holder is also helpful.
Avoiding Over-Tightening: Avoid over-tightening, which can strip the screw head or damage the composite. Tighten the screw until it's snug but not forced.

FAQs

What is the best type of screw for composite decking?

Specifically designed composite decking screws offer the best performance and minimize the risk of damage.

Can I use regular wood screws for composite decking?

While you might get away with it on softer composite materials, it’s strongly discouraged. Regular wood screws are more likely to strip the material.

How do I prevent splitting composite decking when screwing?

Pre-drilling pilot holes is the most effective way to prevent splitting.

What should I do if I strip a screw hole?

If you strip a screw hole, you may need to use a larger diameter screw or use a wood filler to repair the damaged area before reinstalling the screw.

Conclusion

Choosing the right screws is vital for a successful composite decking project. By understanding the different types of screws available and following the installation tips above, you can ensure a strong, beautiful, and long-lasting deck for years to come. Remember, investing in high-quality screws designed specifically for composite decking will pay off in the long run.