Details Landscape Art, a Sonoma County landscape contractor, designs and builds gardens in a variety of topographical situations. The North Bay, and, in particular, Sonoma County, is a hilly area, with grades ranging from flat to gentle slopes to steep cliffs. Pressure-treated steps are a technique we use to move up and down these sloped areas.
With the scarcity of land in California, we frequently see housing developments built right into the hillsides, with two and three story homes with entrances on different levels. Landscaping on these sloping yards can be challenging, and are usually dealt with in one of two ways. The first is excavation and grading, creating flat areas supported by retaining walls. This is the subject of another blog.
The second is the construction of steps to transition from one level to another. If there is other hardscape work on the property, such as patios, walkways or driveways, which are constructed using flagstone, exposed aggregate, brick or stamped concrete, we generally build the stairs using the same materials so all the hardscape is consistent. Mixing too many different materials on a project is not a good design style, in our humble opinion.
We also build pressure-treated steps, however, using 6 x 6 timbers. We cut them to length, usually three to four feet long, and attach them by driving sixteen inch rebar spikes through pre-drilled holes deep into the ground. Each timber is leveled and plumbed. The slope is pre-cut to accommodate the steps, and laid out according to the degree of the slope and the length the stairs must span. This will determine the spacing between the steps. The steeper the slope, the closer together the spacing needs to be. We try to set them at a comfortable distance apart for people to climb or descend comfortable. This spacing, or ‘tread’, can later be filled with decomposed granite, creeping ground cover such as baby tears, or embedded gravel. The riser is always six inches – that is the dimension of the pressure treated timber. If there is to be a long set of pressure treated steps, we will try to break up this staircase with a landing or two. This serves to give people a place to pause or rest on the way up or down. If the homeowner is elderly or disabled, or if the slopes and steps are too steep and dangerous, we can always arrange to have railings installed for safety. We do not install wrought iron railings, but we have an excellent resource who does.
The stairs can be straight down or be staggered or even gently curved as they descend, meandering down the slope with small plants on the sides. We like to make an informal dry stack wall on the sides of the steps as shown in the photo above. The result is a set of stairs with an informal feel. The wood of the pressure-treated steps, although in contact with the soil, resists rotting and will last and look beautiful for many many years.