A modular staircase frame is lightweight, adjustable, and may be brought to a worksite in pieces to be assembled. The modular staircase frame includes two opposing sets of laterally spaced blades, which may be adjustably connected to form laterally spaced ascending frame members. The opposing sets of blades may include a first pair of blades and a final pair of blades to anchor the frame to a first and second surface, respectively. The blades have openings for adjustable attachment of adjacent blades. The frame may also include stiffeners for added structural support. The opposing sets of laterally spaced blades may further include one or more corner blades for changing the direction of the staircase. Once the frame is installed, treads (temporary or final) can be removably installed on the frame to create a staircase.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A retractable staircase having a first side stringer and a second substantially parallel side stringer connected to a plurality of steps. The first side stringer is fixedly attached to a wall and the second side stringer is pivotally movable about the first side stringer between an extended position, where the steps lie substantially horizontally between the stringers, and a retracted position where the steps lie substantially vertically between the stringers. The retractable staircase also includes a collapsible handrail and a gate that are interconnected with the side stringers and the pivoting steps so that when one of them is moved, the other two move substantially simultaneously.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A prefabricated concrete form with vertical spacers between fill forming cladding with cut-outs in the spacers having horizontal rebar received therethrough and received therein. Stand-offs are provided between the vertical spacers with vertical rebar received on the stand-offs. In one version, the stand-offs are attached to the horizontal rebar. In other versions, the stand-offs are attached to the spacers. A cut-out is formed in one of the claddings to form an auxiliary fill space on the outside of the cladding, which when filled with concrete, upon hardening, forms a ledge for supporting a stair structure.

A deck apparatus for assembly with a pair of opposing brace frames interconnected by a pair opposing connector bases and a deck board top frame having a plurality of deck boards disposed thereon, the connector bases having opposing posts for being received in openings in a lower end of the opposing brace frames ends and the deck board top frame having posts for being received in an upper end of the opposing brace frames, and optionally attaching a stairs riser having a plurality of spaced-apart treads or a ramp riser for extending from a deck surface at a height to a vertically lower support surface.

A method of increasing usable space in a parking lot. A support assembly and an access system are erected. A module is placed on the support assembly in one piece or section-by-section. There is an accessible volume of space below the module that is sufficient to allow an automobile to park in a parking space below the module or to allow an automobile to drive in a drive aisle below the module. The module is removably connected to the support assembly. The module may include a frame and a covering coupled to the frame. The support assembly may include portions positioned between adjacent parking spaces of the parking lot. One portion of the support assembly may be positioned on one side of a drive aisle with another portion of the support assembly positioned on the opposite side of the drive aisle.