Composite Decking Step Construction

The following instructions are a guide for Composite Decking Step Construction using Ecodek® composite decking boards, please work in conjunction with Building Regulations (specifically, Part K) if you need to do so.

You may also need to add balustrade, consult with Building Regulations or local planning officer for guidance.

Composite Decking Step Construction -Timber Framed

You can buy pre-fabricated stringers from DIY shops or you can make your own from timber planks, we would advise using 6”x 2” C16 pressure treated timbers.

You can use UK Composite Decking deck boards 2-up to make the step surface (also known as the ‘going’).

If you butt the boards together, then you will achieve a total ‘going’ of 276mm (total ‘going’ allowed is 223mm – 300mm). The ‘nosing’ or overhanging front lip of the step must be at least 16mm. The difference in height between 2 consecutive steps (also known as the ‘rise’) must be between 165mm and 200mm in this situation.

Ensure bearer spacing is 400mm max, 2 screws per board, per bearer.

Step sub-frame should be securely anchored to the ground, preferably on concrete pads.

Composite Decking Step Construction

Covering Concrete Steps with deck Boards

When covering concrete steps with composite decking boards, it is imperative to leave at least a 10mm drainage cavity under the deck boards and where the inside edge of the deck board meets the riser.

If you wish to clad the risers also, then you will need to lift that 10mm off the surface as well. This is to ensure that water has a free and easy route down the back of the Ecodek steps (& rise covers if fitted).

In this example, we have used our 10mm x 36mm insert strip as a packer between the concrete and Ecodek® deck boards, you could use any other waterproof media such as plastic or stiff rubber.  In this situation, you cannot use composite deck screws and must instead use a concrete approved screw such as ‘Tapcon®’.

The concrete screw must go through the decking, packer and into the concrete holding the whole assembly in compression. 2 screws per deck board, per packer.  You may have to check whether your steps comply with Building Regulations.

Composite decking - Concret Steps



Safety Advice Note:
We strongly recommend the addition of anti-slip, high-visibility stair nosings when constructing steps