Joists & Battens

BM Steel’s Plastic Cladding Battens are made from 100% recycled materials and are the best battens to use for Composite Cladding. We stock battens in two different sizes.

Use a combination of steel fixings and concrete anchors or opt for an adjustable pedestal system. This allows precise levelling and avoids direct contact between the joist and the concrete, reducing water retention.

They are more fire-resistant than untreated timber, but not fully fireproof. For commercial installations, always check whether your project requires materials with specific fire ratings and request data sheets as needed.

Yes, like most composite materials, recycled plastic battens will expand and contract slightly depending on external conditions. Always refer to manufacturer guidelines for recommended expansion gaps during installation.

Cladding battens are typically slimmer and fixed vertically or horizontally to support cladding boards, whereas decking joists are heavier-duty and laid horizontally as the structural base beneath decking surfaces.
 

While plastic joists are excellent for ground-level or low-height decks, for elevated or load-bearing structures, consider combining them with galvanised steel or treated timber cross-supports to provide added strength.

Yes, but you’ll need to level the ground first or use adjustable pedestal supports to create a consistent base. Uneven ground can lead to deck instability or pooling water, so ensure a level surface before joist installation.

Attach Cladding Battens to the supporting wall or structure at 600mm intervals, with the first batten being installed at least 20mm from the ground. Secure the first Cladding Panel to the battens using Cladding Clips, and then line up the second board and slide it into place. Repeat these steps for the remaining panels.

The size of the battens you should use for cladding depends on the size of the structure as well as the size of the cladding boards. Choose from 100 x 20 x 2800mm and 50 x 25 x 3000mm Plastic Cladding Battens at BM Steel.

A joist is a length of material, for example recycled plastic, that provides the essential framework needed for attaching the decking boards. Joists can sit directly on the ground, or you can use them with BM Steel’s Pedestal system.

A Cladding Batten is a length of strong, durable plastic used for the installation of and support for exterior Composite Cladding.

Level joists for Composite Decking by raising them to the required height. Do this by placing noggins underneath them.

The size of the joists you use depends on the size of the decking boards as well as the size of the deck. BM Steel offers Plastic Decking Joists in two sizes: 125 x 50 x 3000mm and 50 x 50 x 2400mm.

Yes, joists need an expansion gap. Leave a gap of at least 8mm between joist ends at butt joints. and leave a gap of at least 15mm between joist ends and fixed objects such as walls.

The distance between joists depends on the make of the Composite Decking. As a good rule of thumb, joists should be at spacings of between 250-350mm.

Yes, you can lay Composite Decking on Plastic Joists. Order top-quality Joists from BM Steel online for fast, friendly service.

Follow these steps to install joists. Firstly, outline the area and mark a grid layout. Evenly lay the plastic post network, spacing posts at 1,000mm intervals. Dig holes and cement the posts into the ground (a third of their length deep) to fix them to the base, ensuring the posts are upright and level with each other.

Form a cross-bearer network along the posts’ length with the large plastic joist. Leave a 125mm gap above the bearer to accommodate joist thickness. Fix the bearers to the posts securely, leaving a 10mm expansion gap. Lay the joists directly onto the bearer network, leaving spacings between 250-350mm. Start by installing the outside joists to the subframe and then fix joists along the bearer network. Fix the joists by screwing diagonally through them into the bearers. Use a double joist for enough support where two decking boards are expected to meet.