A Guide To Millboard’s Decking Subframes 

Although hidden, your deck’s subframe is one of the most essential elements of your decking structure to guarantee stability, durability, and easy installation. As we say with turf, it all comes down to preparing the foundations correctly. And that’s precisely what your subframe is – your decking’s foundation.

The great minds at Millboard have not only created stunning composite decking as an elegant landscaping alternative to timber, but they’ve also developed three different types of subframes to support your decking structure – whatever size or shape!

What Is a Decking Subframe?

A subframe for decking is a structure that sits between the ground and your decking boards. It acts as a base for your boards to attach to and supports the overall structure of your decking. Millboard’s high-end subframes serve many purposes, including:

• Creating the shape of your deck
• Holding decking boards in place
• Supporting weight distribution
• Lifting decks off the ground
• Raising decking to your ideal height
• Preventing movement over time
• Maintaining your decking’s longevity

How Many Types of Subframes Does Millboard Have?

Millboard offers three types of subframes, which we supply here at George Davies. This means that when you order your beautiful Millboard composite decking, you can also order the correct subframe at the same time, and all items will be delivered together. The three different types of subframes are Plas-Pro, DuoSpan, and DuoLift.

Millboard’s Three Types of Subframes

Plas-Pro Subframe

Millboard’s Plas-Pro Subframe is their premium decking structure. Made from 100% recycled plastic, it’s an ideal solution for individuals and companies seeking a fully sustainable decking option. Its plastic makeup also means it’s highly flexible and can be used in various locations. It’s ideal for areas prone to dampness or water exposure, as the material is resistant to rot.

By utilising selected, graded materials and an innovative engineering process, Plas-Pro provides exceptional strength, long-lasting durability, and all-weather resistance. With four different types of Plas-Pro subframes, landscapers often use it when installing new decking structures or strengthening existing ones.

Types of Plas-Pro Subframes:

• Subframe 01: Used to install decking over soil or an earth base.
• Subframe 02: Used in conjunction with DuoLift over solid, stable ground.
• Subframe 03: Used on low-level areas with a solid, stable base (should not be raised with cradles).
• Subframe 04: Used with Subframe 01.

Where To Use Plas-Pro Subframes:

• High-moisture areas
• Domestic gardens
• Social and community areas
• Areas near water or swimming pools
• Roof terraces
• Coastal areas
• Locations with high humidity
• Projects where sustainability is key

DuoSpan Subframe

Millboard’s DuoSpan subframe offers two functions: a sturdy foundation for Millboard composite decking and a universal support system for outdoor flooring – due to its incredible strength, versatility and weight-bearing qualities. Made from aluminium and recycled plastics, it combines the strength of metal with the flexibility of plastic, allowing it to support a range of decking shapes and sizes.

One of DuoSpan’s key features is its easy installation setup, which includes a range of beams, joists, brackets, and connectors to support your decking design and accommodate various angles. It also has top-down fixing of boards, screw-locating grooves and self-drilling screws suiting any level of installation skill.

Where to Use DuoSpan Subframe:

• Domestic and commercial decking structures
• In conjunction with Plas-Pro for curved decking
• Decking that requires optimal support
• Unique shapes and decking designs
• Statement decking projects

DuoLift Subframe

Millboard’s DuoLift is a support system that works in conjunction with other subframes to easily and effectively raise decking levels. A non-wood alternative, it provides peace of mind that your decking’s subframe won’t rot, split, or warp – creating a strong, resilient, and long-lasting foundation suitable for all locations.

DuoLift Components:

• Joist cradle (15mm–60mm): Adjusts height while in place and locks securely.
• Self-levelling joint (20mm): Levels a subframe or provides a joint for higher support.
• Risers (45mm): Increase decking height.
• Foot (45mm): Adds stability to elevated decks and spreads load weight.
• Acoustic Separation Pads (3mm): Made from cork and recycled rubber to reduce sound and vibration.

Other Types of Decking Subframes

Timber is another common and popular choice for a decking subframe. It’s easy to cut and secure, and often cost-effective. However, not all timber is suitable. As it’s a natural material, it’s prone to rotting. Unlike Millboard’s subframes, timber also requires gaps within the structure to increase airflow.

Things to Consider When Choosing Your Subframe

• Location: Will your deck be near water, against a building, or exposed to weather? Choose a subframe that suits your environment.
• Deck size and design: Large or complex decks need stronger subframes like DuoSpan.
• Deck height: Higher or multi-level decks require robust support. Consider DuoSpan with DuoLift risers.
• Usage: For high-traffic decks, select a heavy-duty subframe.
• Design look: Simple decks can use Plas-Pro; for curved or stepped decks, go with DuoSpan.

Speak to the Millboard Experts

Selecting the right subframe for your composite decking is an essential step to increasing its durability, performance, and longevity. Millboard’s subframes offer flexible solutions to match your decking and landscaping requirements, and you can purchase everything you need right here.

If you’re still unsure, get in touch with our helpful customer service team.

For landscapers, be sure to check out our George Davies Trade Account to support your future orders.

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