A ceiling ladder having a plurality of sections that can be climbed by a user when in an unfolded position into an attic and that can be folded together into a retracted position to be stored above the ceiling. The ladder has a deep step, which has a width greater than the width of other steps of the ladder, in which is located between about 2-5 feet from the floor when the ladder is in the unfolded position so user can stand on the deep step in place objects into the attic without having to climb into the attic. A method. A deep step.

A ceiling ladder having a plurality of sections that can be climbed by a user when in an unfolded position into an attic and that can be folded together into a retracted position to be stored above the ceiling. The ladder has a deep step, which has a width greater than the width of other steps of the ladder, in which is located between about 2-5 feet from the floor when the ladder is in the unfolded position so user can stand on the deep step in place objects into the attic without having to climb into the attic. A method. A deep step.

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 ceiling ladder having a plurality of sections that can be climbed by a user when in an unfolded position into an attic and that can be folded together into a retracted position to be stored above the ceiling. The ladder has a deep step, which has a width greater than the width of other steps of the ladder, in which is located between about 2-5 feet from the floor when the ladder is in the unfolded position so user can stand on the deep step in place objects into the attic without having to climb into the attic. A method. A deep step.

A method is disclosed of attaching a tread assembly of a spiral staircase to a vertical support column. One step of the method involves providing a tread assembly having a tread portion attached to an arcuate mounting plate defining at least one hole through which extends a fastener defining external threads, the mounting plate having a first face defining a first radius of curvature. Another step involves providing a support column extending along an axis, the support column having a plurality of axially and angularly spaced apart tread attachment locations, each of the tread attachment locations having an arcuate outer surface defining a corresponding aperture for receipt of the fastener, the arcuate outer surface defining a second radius of curvature that is greater than the first radius of curvature. According to another step of the method, the tread assembly is loosely connected to one of the tread attachment locations of the support column. According to another step, the fastener is tightened such that the arcuate mounting plate of the tread assembly is elastically deformed to be in substantial engagement with the tread attachment location and applies tension to the elongate fastener to inhibit loosening thereof.

A method is disclosed of attaching a tread assembly of a spiral staircase to a vertical support column. One step of the method involves providing a tread assembly having a tread portion attached to an arcuate mounting plate defining at least one hole through which extends a fastener defining external threads, the mounting plate having a first face defining a first radius of curvature. Another step involves providing a support column extending along an axis, the support column having a plurality of axially and angularly spaced apart tread attachment locations, each of the tread attachment locations having an arcuate outer surface defining a corresponding aperture for receipt of the fastener, the arcuate outer surface defining a second radius of curvature that is greater than the first radius of curvature. According to another step of the method, the tread assembly is loosely connected to one of the tread attachment locations of the support column. According to another step, the fastener is tightened such that the arcuate mounting plate of the tread assembly is elastically deformed to be in substantial engagement with the tread attachment location and applies tension to the elongate fastener to inhibit loosening thereof.

A method is disclosed of attaching a tread assembly of a spiral staircase to a vertical support column. One step of the method involves providing a tread assembly having a tread portion attached to an arcuate mounting plate defining at least one hole through which extends a fastener defining external threads, the mounting plate having a first face defining a first radius of curvature. Another step involves providing a support column extending along an axis, the support column having a plurality of axially and angularly spaced apart tread attachment locations, each of the tread attachment locations having an arcuate outer surface defining a corresponding aperture for receipt of the fastener, the arcuate outer surface defining a second radius of curvature that is greater than the first radius of curvature. According to another step of the method, the tread assembly is loosely connected to one of the tread attachment locations of the support column. According to another step, the fastener is tightened such that the arcuate mounting plate of the tread assembly is elastically deformed to be in substantial engagement with the tread attachment location and applies tension to the elongate fastener to inhibit loosening thereof.