How to Build an Apron Stair Design

Stair Building Basics

• A stair apron is a piece of wood that forms a vertical surface below the landing tread, which is the bottom step’s surface. Some stairways also have aprons along the surface of the upstairs flooring covering the topmost step’s riser. Aprons are decorative rather than load bearing, which means that stairway designs with aprons require stringers forming the staircase sides providing additional support in the middle of each step. Treads and risers respectively form stairs’ horizontal and vertical members. The dimensions of each component depend on the staircase’s size, style and shape.

Measuring for the Apron

• During the design process, determine the stairway apron’s size. This lets you install the apron at the right time in the construction process before the project is finished. The apron is the same width as each individual riser matching the width of the staircase. It can be thin, since it doesn't support any weight. Three-quarter inch aprons are common. The apron’s height is slightly taller than each riser’s height, since it fits into a notch cut in the landing tread’s bottom, which secures the apron in place.

Apron Construction

• Cut the wood to size once you know the apron’s dimensions. Since an apron is covered by the landing tread's top nosing and sits flush against the floor, there's no need to finish the edges or add decorative elements. The apron is important for its surface. If you plan to stain the wood, select a piece of lumber with an attractive grain pattern. If you want to paint the apron blending into the floor or matching carpeted stairs, simply cut it to size with a table saw or circular saw and apply several layers of paint before installation.

Apron Installation

• Once the stair's stringers are in place, add the riser below the landing tread. This serves as a backing for the apron, which is also nailed to the ends of the outermost stringers. If the floor is carpeted, cut away the carpeting directly in front of the bottom riser, making space for the apron’s width. Molding or a railing post may install in front of the apron and hide the nail holes, so there's no need to cover or fill them until the stairway is finished.