Decking Grooves: Up or Down?

Decking boards – grooves up or flat side up? Short answer is grooves up.

However, the debate over whether decking grooves should face up or down has sparked discussions among DIY enthusiasts and professionals alike for many years. According to the Timber Decking & Cladding Association, the answer largely depends on the type of decking board you have, with dual-sided boards offering the flexibility to choose based on personal preference and specific project needs. However, a poll conducted on Reddit shows that most people would still install decking with the groove on the upper side. 

Debunking Decking Ridge Myths

Despite popular belief, the correct way to install decking boards is with the ridges facing down, according to manufacturers and professionals in the industry. This orientation serves several important purposes:

• • Improved airflow: The ridges on the underside of the board allow for better air circulation between the decking and the supporting structure.

• • Moisture management: With ridges facing down, water is less likely to accumulate in the grooves, reducing the risk of rot and mould.

• • Structural integrity: The downward-facing ridges contribute to a stronger overall structure.

• • Enhanced drying: This configuration allows for better drainage and air drying of the deck surface.

Contrary to common misconceptions the ridges are not designed for aesthetic purposes or to increase traction. In fact, installing the boards with ridges facing up can lead to several issues:

• • Moisture accumulation: Water and debris can collect in the upward-facing grooves, potentially leading to rot and mould growth.

• • Reduced comfort: Walking barefoot on grooved surfaces can be uncomfortable.

• • Cleaning difficulties: Debris trapped in the grooves can be challenging to remove.

It’s worth noting that some modern decking boards are double-sided, offering different textures on each side to accommodate various preferences. However, even with these options, manufacturers generally recommend installing the boards with the grooved side down for optimal performance and longevity.

To address concerns about slipperiness, alternatives such as anti-slip decking strips or treatments with anti-slip properties can be more effective than relying on the grooves for traction. Proper maintenance, including regular cleaning and sealing, is crucial for preserving the deck’s appearance and functionality, regardless of the board orientation.

Purpose of Decking Ridges

Decking boards feature ridges, also known as grooves or reeds, that run along their length. These ridges serve specific functional purposes, although they are often misunderstood and incorrectly installed.

Despite these intended functions, many people mistakenly install the boards with the ridges facing up for several reasons:

• • Aesthetic appeal: The grooved patterns can create an interesting visual effect that some find attractive.

• • Perceived functionality: There’s a common misconception that upward-facing ridges provide better traction or slip resistance.

However, manufacturers consistently recommend installing the boards with the ridges facing down. This orientation aligns with the design intent and offers several benefits:

• • Improved air circulation underneath the deck

• • Better water drainage

• • Reduced risk of moisture-related damage

• • Smoother surface for walking barefoot

It’s important to note that some modern decking boards are designed with different textures or patterns on both sides, allowing for installation flexibility based on personal preference. However, even with these dual-sided options, the general recommendation is to install the boards with the grooved side down for optimal performance and longevity.

Ineffective Anti-Slip Decking Solutions

Many homeowners and contractors attempt various short-term fixes to prevent slipping on decking, but these methods often prove ineffective, costly, and potentially hazardous. 

Here’s an overview of common approaches and their drawbacks:

• • Grit and anti-slip coatings:
    • • Require thick application to hold grit particles
    • • Wear down quickly, losing slip resistance
    • • Often unattractive, obscuring the deck’s natural appearance
    • • Need extensive curing time (up to 24 hours)
    • • Grit tends to be kicked out after a few months of use

• • Non-slip tape:
    • • Not suitable for outdoor applications
    • • Deteriorates rapidly in exterior conditions
    • • May cause damage to the decking surface

• • Chicken wire:
    • • Presents a significant trip hazard
    • • Can break easily, creating sharp edges that may cut feet and ankles
    • • Considered a “cutting corners” method that’s ineffective and dangerous

• • Rubber mats:
    • • Become slippery when wet
    • • Can slip around if not properly secured
    • • Trap dirt and debris, making maintenance difficult
    • • Some improvised solutions, like old conveyor belts, can be extremely slippery when wet

These makeshift solutions are often short-lived, requiring frequent replacement and potentially causing more problems than they solve. They can contribute to slip hazards rather than mitigating them, and many fail to meet health and safety requirements for outdoor spaces.

For effective and long-lasting slip resistance, specialised solutions designed for timber and decking are necessary. One recommended option is the installation of GRP (Glass Reinforced Plastic) Non-Slip Decking Strips, which provide durable traction without compromising the deck’s appearance or integrity.

When considering anti-slip measures for decking, it’s crucial to prioritise safety, durability, and compatibility with the decking material. Professional-grade solutions that meet relevant safety standards are typically the most effective and cost-efficient in the long run.

Effective Anti-Slip Decking Solutions

To effectively prevent slipping on timber decking, long-term solutions are essential. One of the most reliable options is Engineered Composites GRP (Glass Reinforced Plastic) Anti-slip 4.0mm Sheets and Decking Strips. These products offer several advantages over short-term fixes:

• • Durability: Ourt anti-slip products are highly durable, with many customers reporting excellent performance even after 10 years of use. The strips and sheets maintain their effectiveness and appearance over time, showing minimal signs of wear and tear.

• • Customizable sizing: The strips can be cut to fit most standard decking board sizes, typically 145mm or less, ensuring a proper fit for various decking configurations.

• • Versatile application: These anti-slip solutions can be applied to cover the entire deck surface, partial areas, or in a staggered pattern, depending on specific needs and preferences.

• • Proven effectiveness: GRP composite anti-slip products have demonstrated superior slip resistance on decking boards, significantly reducing the risk of slip-related accidents.

• • Long-term cost-effectiveness: While the initial investment may be higher than temporary solutions, the longevity and performance of these products make them more economical in the long run.

Installation options for anti-slip products include:

• • Full coverage: Applying strips or sheets to the entire deck surface for maximum slip resistance.

• • Partial coverage: Strategically placing strips on high-traffic areas or potentially slippery zones.

• • Staggered pattern: Installing strips in an alternating pattern for a balance of aesthetics and functionality.

When considering anti-slip solutions for decking, it’s crucial to prioritise long-lasting, effective products that maintain the deck’s appearance while significantly enhancing safety. GRP anti-slip sheets and decking strips offer a reliable solution that addresses these concerns, providing a permanent reduction in slip hazards for timber decking.

For optimal results, it’s recommended to follow manufacturer guidelines for installation and maintenance of these anti-slip products. Professional installation may be advisable for large or complex decking areas to ensure proper application and maximum effectiveness.