Specialist Cantilevered Decking for a Pontoon and Boardwalk


Specialist Cantilevered Decking for a Pontoon and Boardwalk

Having already completed projects for several Architects; Exterior Decking were asked to supply and install a Millboard decking structure for a private client’s property.

This decking installation project was a little more complex than the normal installation; it required structural load calculations to support the steel cantilevered cradle that the decking structure is to sit on.

The concrete pad-stones created to site the steels on were 8 tonnes for the securing base and 6 tonnes for the fulcrum. The concrete structures were formed from reinforced poured concrete into a shuttered former to create the shape.

The steel structure, hot dipped galvanised and predrilled to be correctly aligned onto the concrete pad stones, lifted into place via a crane.

Recycled plastic joists for a decking structure.

HDPE, High Density Polyethylene. That’s the material the joists are constructed from. The normal TRADA endorsed joist/beam span tables can’t be used for this product as they behave differently. The span for the beams 120mm x 60mm is 1.5 metres and 120 or 100 x 40 have a span max’ of 1m. The posts are the same material but with a dimension of 125mm x 75mm

All of which must be bolted with either M10 or M12 bolts, nuts, square washers and shake proof washer or split ring washer.

Why use Plastic joists?

The simple reason is that they last for about a million years with no corrosion, rotting, warping or splitting, nothing eats them and they are not harmed by constant emersion in water. So the extra cost is bourne out by the longevity of the product. A cost comparison, assuming 68 square metres of deck the cost of the timber would be approx £900 compared to £3400 in plastic.

For more decking or plastic joist information contact us at Exterior Solutions Ltd 01494 711800

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