Patent ID: 8707638

Claim:
A staircase comprising: a first staircase stringer, the first staircase stringer comprising a plurality of riser channels, each of the plurality of riser channels comprising a riser channel width sufficient to encompass a thickness of a sub-riser and a thickness of a capping riser in each of the plurality of riser channels; the first staircase stringer further comprising a plurality of tread channels, each of the plurality of tread channels comprising a tread channel width sufficient to encompass a thickness of a sub-tread and a thickness of a capping tread in each of the plurality of tread channels; a second staircase stringer, the second staircase stringer comprising a plurality of riser channels, each of the plurality of riser channels comprising a riser channel width sufficient to encompass the thickness of the sub-riser and the thickness of the capping riser in each of the plurality of riser channels; the second staircase stringer further comprising a plurality of tread channels, each of the plurality of tread channels comprising a tread channel width sufficient to encompass the thickness of the sub-tread and the thickness of the capping tread in each of the plurality of tread channels; the staircase further comprising sub-risers and sub-treads fixed in corresponding riser channels and tread channels of the first and second stringers in a first procedure to form a staircase comprising the first and second stringers assembled together with the sub-risers and sub-treads; and the staircase further comprising capping risers and capping treads dimensioned to be installed over the sub-risers and sub-treads in a second procedure, wherein each of the plurality of riser channels comprises a sub-riser channel at a first depth and a capping riser channel at a second depth less than the first depth, and each of the plurality of tread channels comprises a sub-tread channel at a first depth and a capping tread channel at a second depth less than the first depth.