How to Build Floating Outside Stairs

Center Support

• 1

  Measure the width of your stairwell opening. Make a mark at the center.

• 2

  Draw a plumb vertical line through the mark at the lip of the opening.

• 3

  Have a helper hold the base of the center pole. Center the header plate over the vertical line. Position the plate 1 inch below the landing.

• 4

  Drill holes for the screws or lag bolts. Drill the screws or bolts into the wood.

• 5

  Align the support so it's exactly parallel to the adjacent wall.

• 6

  Bolt the base plate to the floor. Drill bolt holes with a masonry bit, if you have a concrete surface. Screw the lag bolts through the holes in the base plate and into the floor.

• 7

  Determine your riser height. Measure from the top of your header straight down to the floor. Divide this number by the number of treads on your stairs plus 1. This gives you the height of each riser.

• 8

  Set the bottom locking sleeve, a part of the support that keep the treads locked securely in place, and the metal tread support at your riser height minus 1 inch.

• 9

  Pull the locking sleeve up and set it in position. Place the tread support on top of the locking sleeve. Fasten it to the locking sleeve with steel bolts screwed through the aligned pre-drilled holes. Check for level.

• 10

  Place the next locking sleeve in position and align the tread support. Fasten with steel bolts. Check for level. Install the other tread supports in the same manner.

Treads

• 11

  Center a wooden tread over the bottom tread support. Ensure that the back of the tread is flush with the center pole.

• 12

  Fasten the tread to the tread support with screws drilled into the wood from the underside of the center pole.

• 13

  Fastens all the treads to the tread supports the same way you did the bottom tread.

Railing

• 14

  Ensure that you set the railing on the side opposite the wall.

• 15

  Measure 2 1/2 inches inward from the outside edge of the bottom tread and draw a line. Make a mark on this line at least 2 1/2 inches from the front and back of the tread.

• 16

  Set a spindle over the mark. Fasten it to the tread with wood screws drilled through the holes in the base plate. Ensure that the flange on top of the spindle points upward.

• 17

  Place the top spindle in position as you did the bottom.

• 18

  Place the handrail over the top and bottom spindle. Have a helper set it so that the handrail reaches 4 inches past the top spindle. Mark the railing 4 inches past the bottom spindle.

• 19

  Cut the handrail at the mark with a hacksaw. Place plastic end caps over the ends of the handrail.

• 20

  Position the handrail over the top and bottom spindle with a 4-inch overhang on each end. Check the spindles for plumb. Fasten the handrail to the top and bottom spindles by drilling screws through the handrail into the pre-drilled holes of the metal flanges.

• 21

  Set the intermediate spindles on the other tread as you did with the top and bottom spindle. Fit them into the grooves on the underside of the handrail.