How to Do Skirts for Stairs

Pit the board on top of the stair treads against the wall. Nail the board in place, leaving a small part of the nail exposed for easy removal. Mark a line on the wall over the top edge of the board, above the top and bottom stair treads.

Put the carpenter's scribe vertically against the wall and the highest stair riser. Mark the top of the stair on the skirt board and using a ruler, draw a line through the board, including the mark. Drive a nail through the carpenter's scribe, skirt and wall, enough to mark the wall lightly. Repeat for all the stair risers. Remove the skirt board from the wall.

Cut the skirt board at the lowest scribe mark. The angle of the board should match the angle of the stairs. Place the skirt board back against the wall, stairs and floor.

Put the carpenter's scribe horizontally against the floor, wall and first riser. Anchor the scribe through the skirt and wall with a nail. Mark the end of the scribe against the skirt and draw a line up to meet the height of the next riser, using a ruler. The mark should match any overlap of each stair. Repeat for all of the steps.

Remove the skirt from the wall and fill in any empty spaces in the tracing of the steps. If you have or plan on installing carpeting or flooring on the stairs, add 1/4 inch of space at each of the top tread cuts on the skirt.

Cut the skirt and sand the edges. Put the skirt against the wall and stairs to check for gaps or high areas and trim until the skirt lies flush against both the wall and stairs.

Put the skirt against the stairs and set a level vertically against the first stair riser and the wall. Mark a vertical line through the skirt.

Mark a second line at the top of the stairs, laying the level vertically against the wall and lining it up with the riser of the top riser. Mark a vertical line through the skirt.

Cut off both marked pieces so that the skirt matches the shape of your stairs.