1 Total costs (materials plus shipping and labor) for installing a straight, return or L-shaped stair can run $1,300-$7,000 or more. 2  Materials plus labor for custom-built wooden stairs, such as a sweeping circular or elliptical design, can cost $10,000-$30,000 or more, depending on the size, style and type of wood.
Make another bleach solution and pour it onto the driveway. Wait 20 more minutes for the bleach to kill the mold. Rinse the driveway thoroughly with a garden hose. Prevent future mold with a borate solution. Mix 1/4 cup of borate detergent with 1 gallon of warm water in a bucket. Pour the solution onto the driveway and allow it to dry. Don't rinse it.
Scrubbing it off with a push broom doesn't take care of the problem either. You have two effective options for removing mold and mildew from concrete. 1. Scrubbing With Bleach. Combine 1/4 cup of liquid bleach with 1 gallon of hot water in a large bucket. Using non-diluted bleach may work, but mixing it with water is more conservative and less likely to cause damage to your sidewalk.