Building an Exposed Basement Staircase

Measurements

• 1

  Measure the distance between the stair header and the basement floor in inches with a tape measure. This gives your total rise for the stairway.

• 2

  Divide the total rise by 7 to get the total number of steps in the stairway, rounding off the fraction. Then divide the total rise by the number of steps to get the unit rise, the height of each individual riser. This number is typically between 7 and 8 inches and cannot be greater than 8 inches, according to code.

• 3

  Choose a depth, or unit run, for your treads. Keep in mind the combination of unit rise and unit run must fall between 17 and 18 inches and the minimum tread depth is 10 inches. Select a 10 1/2-inch tread depth if your unit rise is 7 1/2 inches, for example.

Stringers

• 4

  Lay a framing square near one end of a 2-by-10 piece of lumber. Lay the square so that the number for the unit run intersects the top edge of the board on the broad leg of the square. Set the other leg of the square so that the number for the unit rise intersects the board.

• 5

  Draw a line around the outer edge of the square. Extend the unit run line to the other edge of the board.

• 6

  Slide the framing square up the board so that the unit run covers the spot previously held by the unit rise. Ensure that unit rise covers a new spot against the edge. Draw a line around the outer edge of the square. Continue up the board shifting the square's position.

• 7

  Extend the last unit rise line all the way to the other edge of the board so it will fit against the stair header.

• 8

  Cut along the header line and the first unit run line with a circular saw. Cut a 1 1/2 inch-by-3 1/2 inch notch in the bottom of the board, where a bottom plate, or kick plate, will fit.

• 9

  Cut along the other unit run and unit rise lines. Make another stringer as you did the first one.

Install

• 10

  Place a stringer against the top of the stairway header and the wall. Nail three 16d nails to the header by end nailing them from behind into the stringer. Toenail two 16d nails through the stringer into the header. Repeat for the other stringer. Check the stringers for plumb and level.

• 11

  Cut a 2-by-4 to length and position it under the notches at the bottom of the stringers. Screw it to the floor.

• 12

  Cut the treads to the proper length and depth from 1-by lumber. Place treads on the stringers. Nail at each side with nail protruding. Check each tread for level. Hammer in nails flush with the stringer, when all treads show level.

• 13

  Find the wall studs with a stud finder. Fasten the stringers to the wall at every stud with a drywall screws.

Handrail

• 14

  Measure from the top of the last tread up to a point 36 inches on the wall and make a mark. Ensure that the mark is over a wall stud with a stud finder. Do the same at the top tread.

• 15

  Unroll the string from a chalk line tool between the marks. Have a helper hold one end of the line taut as you snap the string and leave a chalk line on the wall.

• 16

  Place a bracket in position with its top touching the chalk line.

• 17

  Drill holes in the bracket openings and screw the bracket to the stud. Repeat for the other end of the stairs.

• 18

  Place the handrail along the length of stairs. Make two marks at the top step and bottom tread.

• 19

  Cut the handrail to length using a 45-degree cut with a miter saw. Make the first cut in one direction and the second cut in the opposite direction. Keep the excess from each end and mark one as the bottom and one as the top.

• 20

  Set the handrail in place on the brackets. Measure from the railing to the wall.

• 21

  Cut the excess pieces to this length on the end without the angle. Glue the bottom piece to the top of the handrail and the top piece to the bottom of the rail. Use L-shaped metal connectors as well. These "return" pieces are required by code to avoid having purse straps or other objects getting hooked on the handrail.

• 22

  Place glue on the ends of returns. Screw the handrail into the studs at the brackets. Fit return pieces against the wall.