A method for building modular stair system comprises assembling a plurality of modular stair units, each of the plurality of modular stair units associated with a single story of a construction, each of the plurality of modular stair units further comprising a self-supporting structure supported by a plurality of corner columns. A first modular stair unit is located on a foundation of a structure. The first modular stair unit is secured to the foundation of the structure. A second modular stair unit is stacked on top of the first modular stair unit, wherein a first plurality of corner support columns engage of the first modular stair unit engage a second plurality of corner support columns of the second modular stair unit. The second modular stair unit is leveled using a connection sleeve that slides within the first plurality of corner support columns and the second plurality of corner support columns. The second modular stair unit is connected to the first modular stair unit to maintain the leveled second modular stair unit using the connection sleeve.

A platform system comprising a platform structure having at least one modular platform unit with platform connection features on a side surface thereof to which other components can be connected, the other components including at least two of the following: another modular platform unit, a stair unit, a tower unit, a handrail unit, and a ladder unit. A stair assembly is connected to the platform structure via said connection features, the stair assembly comprising a plurality of stair units connected together to provide a number of steps equal to the sum of steps of the stair units.

A platform system comprising a platform structure having at least one modular platform unit with platform connection features on a side surface thereof to which other components can be connected, the other components including at least two of the following: another modular platform unit, a stair unit, a tower unit, a handrail unit, and a ladder unit. A stair assembly is connected to the platform structure via said connection features, the stair assembly comprising a plurality of stair units connected together to provide a number of steps equal to the sum of steps of the stair units.

A platform system comprising a platform structure having at least one modular platform unit with platform connection features on a side surface thereof to which other components can be connected, the other components including at least two of the following: another modular platform unit, a stair unit, a tower unit, a handrail unit, and a ladder unit. A stair assembly is connected to the platform structure via said connection features, the stair assembly comprising a plurality of stair units connected together to provide a number of steps equal to the sum of steps of the stair units.

A platform system comprising a platform structure having at least one modular platform unit with platform connection features on a side surface thereof to which other components can be connected, the other components including at least two of the following: another modular platform unit, a stair unit, a tower unit, a handrail unit, and a ladder unit. A stair assembly is connected to the platform structure via said connection features, the stair assembly comprising a plurality of stair units connected together to provide a number of steps equal to the sum of steps of the stair units.

A system for securing modular building units to each other and a method for assembling structures using said method is disclosed. The disclosed system allows for modules to be connected to each other from an external position, without a person having to enter the modules to fasten components internally. The system and method may be used to build structures using prefabricated modules, avoiding significant amounts of onsite labor and drastically reducing the time required to erect structures.

An adjustable step system for assisting a person walking up or down a flight of stairs. The system includes adjustable steps that can be mounted to the stairs of the flight of stairs. The adjustable steps effectively reduce the required vertical height of a step that a person is required to take for each stair. The adjustable steps are also movable and can be positioned at a desired location along the width of the stairs when not in use.

A method for building modular stair system comprises assembling a plurality of modular stair units, each of the plurality of modular stair units associated with a single story of a construction, each of the plurality of modular stair units further comprising a self-supporting structure supported by a plurality of corner columns. A first modular stair unit is located on a foundation of a structure. The first modular stair unit is secured to the foundation of the structure. A second modular stair unit is stacked on top of the first modular stair unit, wherein a first plurality of corner support columns engage of the first modular stair unit engage a second plurality of corner support columns of the second modular stair unit. The second modular stair unit is leveled using a connection sleeve that slides within the first plurality of corner support columns and the second plurality of corner support columns. The second modular stair unit is connected to the first modular stair unit to maintain the leveled second modular stair unit using the connection sleeve.

A method for building modular stair system comprises assembling a plurality of modular stair units, each of the plurality of modular stair units associated with a single story of a construction, each of the plurality of modular stair units further comprising a self-supporting structure supported by a plurality of corner columns. A first modular stair unit is located on a foundation of a structure. The first modular stair unit is secured to the foundation of the structure. A second modular stair unit is stacked on top of the first modular stair unit, wherein a first plurality of corner support columns engage of the first modular stair unit engage a second plurality of corner support columns of the second modular stair unit. The second modular stair unit is leveled using a connection sleeve that slides within the first plurality of corner support columns and the second plurality of corner support columns. The second modular stair unit is connected to the first modular stair unit to maintain the leveled second modular stair unit using the connection sleeve.

Systems and methods for constructing staircases are described herein. The systems include a stringer hanger bracket for coupling a stair stringer of the staircase to an upper floor, two or more tread support structures and a jig. Each tread support structure is configured to couple a tread to the stair stringer. The jig is configured to determine a mounting position of each of the tread support structures on the stair stringer, determine a mounting position of each of the tread support structures on the stair stringer and/or determine a length of the stair stringer.