Or, why I heart my calculator.
If you’re planning on sketching some new garden design ideas in anticipation of spring projects, it takes more than a fresh sheet of vellum, a circle template and sharp drafting pencil - better get ready to do a little math.
There’s a school of thought that ideal gardens should be carefree, plant driven spaces, but the truth is, if the hardscape elements – patios, stairs and pathways – aren’t thoughtfully planned, you haven’t maximized your garden’s potential. A common mistake people make is thinking that exterior space planning principles mimic interior ones, but that’s not the case.
Movement and circulation are completely different outside. Inside, the purpose of hallways, stairs and other open areas is to get easily and quickly from point A to point B to point C, as in, from the couch in front of the T.V. to the kitchen for a snack and up the stairs to the bedroom for a nap. Having just described my perfect Sunday afternoon, I can assure you these are all important activities, and I would be very annoyed if naptime was delayed because of unnecessary detours.
The opposite is true in the garden, where moving through the space is an important part of the experience. In honor of the front yard design plans VW has recently been sharing on her blog, I’m going to focus this post on outdoor stairs. I’ll talk about patios and pathways a little later.
You may not know it, but there is a specific formula for designing a staircase, which is 2R + T = 24” – 27”, where R = rise and T = tread.
For example, if the risers are 6”, and the tread is 12” than your formula will yield 24”. While this falls within the range and is fine for indoors, in the outdoors, the goal is to move people more slowly through the space – again, it’s about the experiencing the garden. Smaller treads with steeper risers have a cramped, utilitarian feel, are less comfortable and encourage people to hurry up. They also accommodate less of the walker’s feet, which means paying more attention, looking down at the steps, etc. instead of looking around at the garden.
My favorite range for garden treads is 14” to 16”. This is wide enough to create a gracious effect and encourage a slower pace, but not so wide as to break someone’s normal stride. 18” treads look beautiful, and also create enough width to sit on comfortably, but they are too wide to accommodate a typical stride, so I would generally use a tread this big if there are only one or two steps. Grade permitting, I like a 5 ½” rise and a 15” tread.
Another outdoor stair mistake includes not marking the edge, inadvertently creating a tripping hazard. People do not pay as much attention when using outdoor steps, so it’s important to mark the edge. This can be done by adding a bullnose finish (creating a shadow) adding a border that is a different material or color or adding a border of the same material but in a different pattern. This is particularly important if you have only one stair, as people tend not to notice them as well.
Contrasting material + bullnose
Tile edge is a different pattern, + bullnose
What else? If you have space, consider adding landings. This signals the walker that s/he is supposed to slow down and enjoy the journey, not just hurry to a destination. If you break up the stairs this way and you want to be super advanced in your design, stagger the number of steps in between landings and plan their size so that people are not always pushing off on the same foot.
staggered stairs with landing
Landing with contrasing border pattern
In the next garden, I used 12" treads because they already existed on the site and I wanted to maximize continuity and not confuse walkers by changing the pattern. My strategy was to balance the narrower treads with broad landings to keep the experience gracious. This dramatically sloped European inspired garden is designed for strolling (there's no grass or play area), so pulling a visitor comfortably through the space was a primary goal.
Here’s a drawing of a design I did when I was first starting out. Visually, these three broad stairs came out beautifully, but they aren’t that comfortable to walk down. If I were designing this today, I would have created a landing and reduced the tread size to 15”.
Finally, can you imagine a worse staircase? It's certainly not to code.
No after photo, as the current state of the economy has meant postponing the installation on this "hang out with the dogs" garden, but here is the design. The three awkward steps have been replaced with one broad step leading to a mini patio, then several broad steps down into the garden.
If all you plant lovers are still with me, I’ll end by saying that I meet a lot of people who think plants are the main thing I spend my time on. The truth is, for a typical design I spend about 50% of my time on circulation and layout, 25% on communication, meeting and site time, and only 25% on plants. Why? Because plants are wonderfully forgiving, but hardscape is not.
Just remember, Math + Creativity = A Beautiful Garden