How to replace garage steps

[Dwight]

I need to replace the steps in my garage to sell my home.

I can do woodworking, but I need to know how to meet the safety standards the buyers are asking for.

The house floor is three concrete blocks higher than the garage floor.

[home improvement guy]

A three-block high wall is 24 inches high. Add the height of the floor joists under the door to the house for an additional 9 1/2 inches plus the thickness of the flooring at about 1 inch. Assuming the garage floor covers the first 4 inches of the bottom concrete block, you get 30 1/2 inches for the total height of the steps. Then I referred to the International Residential Code, stating the minimum riser height for each step is approximately 8 inches, and the tread depth (or "run") is 9 to 10 inches. (Refer to your local and state codes for actual measurements.)

Now you're ready to cut the stairs' stringers from a piece of treated 2-by-10-inch lumber. Dividing the 30 1/2 inches by the height of the required 8-inch riser is 3.81 inches, which is rounded off to four risers for a total of three steps. You can round off the number to make the steps fit, but fractions matter. The height of each riser needs to be within 3/8 of an inch of each other to prevent tripping and possible injury. I did not include the last or top riser because this is the riser from the top step into the home. When measuring the total height of the stairs, measure from the highest point of the concrete floor. Then you can add shims to the lowest part after installation. Each step's tread has to be 9 to 10 inches deep, so you now have three steps times 9 or 10 inches (whichever works best for clearances). I would use the 9-inch figure because the material covering the treads will overhang the riser by about 1/2 inch. The steps will extend from the garage wall by 27 inches.

First make sure the floor is level at this point and the wall is plumb. Anything out of level will make the stairs uneven and unsafe, but as stated before, shims will need to be added. Using a carpenter's square, set one side of the square to 8 inches for the riser and 9 or 10 inches for the tread on the other side. Mark each area to be cut from a piece of 2-by-10-inch lumber. Again, use treated lumber for the stairs' stringer because it will be in contact with the concrete garage floor. Once the stairs' stringers have been cut, the bottom portion of the lowest stringer needs to be cut off to allow for the thickness of the tread material to be used. Either 1/2 inch or 3/4 inch needs to be removed, depending on the thickness of the tread covering. Secure the stringers to the 2-by-10-inch rim joist under the garage door, and then level the bottom of each stringer using treated wood shims. If you have three or more risers, the stairs will need to have a handrail that is no more than 2 3/8 inches wide so it can be easily gripped should someone trip or stumble.