An L-shaped ladder for stairs interior or exterior must comply with all applicable building codes to ensure a structurally sound and safe structure. Straight pieces of wood used to the crossbar 5 x 30 cm. A bar is next to the stairs linking the treads. Make the crossbar with a squad of work, from top to bottom. Cut the crossbar with a circular saw. Use the crossbar finished as a template to mark the wood used for other beams. Place the beams in place. Make the width of the stairway at least 90 cm.
Put the rest in changing directions. Make landing size 3 feet wide by 90 by 120 cm. Accounts length of 4 feet to the crossbar; rely on the ladder for stairs first, to rest. Floor joists used to frame the rest of 5 x 15 cm. Covers joists with 2×6 inch boards or material of the same thickness as the treads. The first set of rails now rests on the landing.
Use tables 3 cm to cut the strips together and tables 5 x 15 cm. cut the material with a circular saw. Performs pre-drill all holes before fixing the pieces in place ladder for stairs. Follow the same procedure to build the staircase leading upstairs. Install handrails as required by building codes.