Unique's standard stair designs consist of four series of
staircases available as interior or exterior models.
3QT Series - three quarter turn spiral stairs in seven standard designs ranging from 4' 6" to 7' diameter.
HT Series - half turn stairs in seven standard designs ranging from 6' 6" to 14' diameter
QT Series - quarter turn stairs
in two standard designs - 14' and 16' 11" diameters.
ST Series - straight stairs available in standard 36" and 42" widths.
Unique's standard stairs have been engineered at a height of 114" and demonstrate impressive weight capacities for both tread and total stair capacity (see our specs page). This is particularly important when considering multiple person occupancy on the stair at one time. For longevity and stiffness all spiral stairs are constructed of multi-laminated all
hardwood plies for the supporting stringer and handrail sets. Depending on the design - typical treads are made of solid 1 1/2' hardwood stock*
with both ends recessed and bolted into their respective stringer mortises along with adhesive to assure a permanent fitment.
All of Unique's hardware is fully concealed to retain the beauty
of the wood stairs.
*Alternative species of hardwoods are available - see our Hardwood Options link on this page