The Oak70.XTRA Interior Spiral Stairkit

Photo of Arke Stairs 70XTRA Spiral Stairkit
The Oak 70.XTRA is an adjustable premier series spiral staircase that features solid Oak wooden stair treads and landing to complement and add style to any interior living space. The horizontal balusters and railing design, surrounding the full length of the staircase, is visually unique when compared to the traditional vertical baluster design of most stairs. The staircase can be easily installed by the homeowner in a single day using common household tools. The Oak 70.XTRA is available in 2 diameter sizes and is available in 2 choices of color… BLACK and WHITE.


  • Standard kit includes 12 oak wood stair treads, a landing, a complete handrail, and all necessary hardware and connectors.
  • Diameters available include a 4’ 3” model and a 5’ 3” model.
  • The height range for the standard kit is adjustable from 99-3/16 in. to 122-7/16 in. and with additional components – purchased separately, can be installed to 82-11/16 in. minimum and a 150-13/16 in. maximum.
  • Powder coat finished painted in either Hi-Gloss BLACK or Hi-Gloss WHITE.
  • Can be installed in a clockwise or counterclockwise rotation.
  • Stair treads and landing are made of solid Oak wood with a natural stain and a polyurethane protective coating.
  • Balcony rail kits are available in matching color and horizontal tubing and railing design.
  • Handrail is manufactured from an aluminum core surrounded by a soft PVC cover to allow the handrail to be curved at the time of installation to accommodate the radius of the staircase.
  • Rise between stair treads is adjustable from 8-7/32 in. to 9-13/32 in.
  • Interior installation only.
  • A complete installation guide is included in all kits.
  • Homeowner should consult with your local building inspector for any questions and specifics related to compliance with the local building codes prior to purchase.

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