Decking

A system for forming a decking substructure over an undersurface, the system comprising a plurality of joist supports, and joists adapted to be fitted thereto,

• wherein each joist support comprises a support body which includes a base wall having a bottom side, a top side and a mounting aperture therethrough from the bottom side to the top side, the support body further including two spaced apart side walls extending from the top side of the base wall such that the support body take the form of a channel with a substantially U-shaped cross section-having an open top and opposed spaced apart open ends, the channel when in use being configured so as to at least partially receive one of the joists therein, the bottom side of the base wall having a planar surface section which defines the outermost surface of the joist support,
• wherein each joist comprises an elongated body having opposed spaced apart ends, a top wall, a bottom wall spaced from the top wall and spaced apart side walls extending between the top and bottom walls, the bottom wall having an outer side that extends in from the side walls to a recess that extends up from the outer side, such that when fitted to one of the joist supports, the outer side lies adjacent to the top side of the base wall of the joist support and the recess overlies the mounting aperture in the base wall of the joist support to allow space for a head of a fastener or connector received through the mounting aperture,
• wherein each joist support further comprises a support mounting formation and each joist further comprises a joist mounting formation, the formations being adapted to cooperate and provide a snap fit type connection between the joist and the joist support, wherein the support mounting formation includes two substantially resilient deformable flange members each extending inwardly from a respective joint support side wall towards the joist support base wall and terminating at a free end, and wherein the joist mounting formation includes a side recess in each joist side wall, each side recess having a lower edge which provides for a shoulder, the free ends of the flange members engaging against the shoulders when joist and joist support are fitted together, and
• wherein each joist support is operable in a first and second mode of installation, wherein in the first mode of installation the planar surface section operates as an abutment surface for seating of the joist support directly on the undersurface, and, in the second mode of installation, the joist support is releasably mounted to a height adjuster by way of the mounting aperture in the base wall.