My clients very often start projects in one of two practical ways.
A very common scenario is the need to surmount a difficult practical "infrastructure" hurdle that stands in the way of “the real” project. An example of this might be an access road required to access a building site, or a retaining wall to create a level hillside bench for the building. In my years working and being educated outside of California, I often poigniantly found roads and landscaping thought of as a kind of preamble to the building experience; a kind of bridge to be traversed on the way to the building.
Whether it appeals to our more romantic sensibilities or not, the vast majority of the time, the general populous of clients overwhelmingly requests buildings that are an end in themselves. The yard exists to serve activities taking place near, or inside, buildings. A few statistics underscore this fact. The EPA estimates the average US citizen spends 90% of their time indoors and I was surprised to find a similar state agency (the California Air Resource Board) estimated the average Californian spends 87% of their time indoors.
Is it any wonder that chronologically and stylistically the building is commonly an experience that precedes the cultivation of outdoor spaces? When the moment comes for a homeowner to consider the outdoors, it usually starts - even in California - with the areas directly adjacent to the place they are spending close to 90% of their time. The building.
Be that as it may, the California environment permits a good deal of outdoor living and I would argue it is often associated with the moments we feel especially alive.
Any home designed in an uncongested area deserves to strongly take advantage of the outdoor living experience, even if the residence is commonly imagined and created before formally cultivating its grounds. In this way, landscaping is often a vital extension of the architecture. There are also often practical structural, life safety, and waterproofing considerations that imply a shared character between the architecture and the nearby landscape. California sites often require building permits where the surrounding landscaping is not coplanar with the living space and an extension of the living area is desired.
In all these ways, the concerns in the areas immediately adjacent to the residence are both practically and esthetically, an outgrowth of the architectural design. This is the world of the deck, the elevated concrete slab, the balcony, the trellis, the pool terrace, and the covered patio. It is common to have many waterproofing concerns at these locations and integrating these elements with the building’s larger esthetic, is a way to avoid some of the most insidious rot provocations we encounter here in California. I have often found this coordinated inner and outer architecture implicated in the most successful architectural designs of our climate. Carlos Scarpa, Irving Gill and, of course, Frank Lloyd Wright are all examples of architects who performed very effectively in what we glibly call a Mediterranean climate. More precisely this California condition should be called a semiarid subtropical desert.
What all this means for home design is that we want the house to "flow" into the backyard for those times of day when the outdoor conditions are arguably more pleasant than anything inside a building.
Often, this is at the margins of the day, with the evening being perhaps the favorite margin. This can mean many different things to different people, but fundamentally it usually implies the yard should feel like some kind of horizontal extension of the interior living space. Why horizontal? This horizontal proximity provides the ability to quickly expand or retract the living experience occurring in the main living space to an adjacent surface. Whether food is being deployed from a nearby kitchen or an awning is deployed over a multi slide door, this horizontal proximity provides a movement to the yard that is not so much a migration as a “minor shift”. If there is a social event, it might simply be an organic expansion.
Of course, the reality in California is also our topography. If you are lucky enough to have a view in your backyard, you also probably have the challenge of some kind of dropoff. In this context, the immediate outdoor space is often about a lighter version of the architecture. In this context, the structural challenges present at the building, are usually still present. Walls are mostly eliminated, but roofs can extend or turn into trellises. Floors are turned into hard surface terraces or deck elements. How shall we navigate what the client wants with the challenges the backyard presents? These myriad challenges could fill many blog posts. Hopefully, there will be future opportunities to discuss other aspects like pools and shade structures. For this article, I will confine myself to an important subject I’ve seen many homeowners encounter almost accidentally. The drop-off. When done correctly, it can be a gracious way to open the house up to a beautiful view or yard. When ill-conceived it can be a costly afterthought of view-blocking guardrails.
The Minimal Solution.
There is no doubt that retaining walls are a major cost factor in the design of a terrace on a hillside. It is worth knowing that many jurisdictions will not require a retaining wall to have a building permit if the height of that retaining wall is less than a certain height. Thirty to thirty-six inches is a popular limitation, but there are often caveats associated with the nature of the slope above the retaining wall. If you are creating terraces for a downsloping backyard, the simple height limitation of the retaining wall itself can sometimes happily be the only thing that triggers a building permit. If this is the case, you will want to simply stay under this height limitation.
The other major concern with terraces is the need for costly guardrails. The code requires you to have a 42" guardrail if you are 30" or more above grade where your terrace drops off. When someone is sitting down on a terrace, this 42" height requirement is right at eye level. Recalling the popular desire of most clients to have a "flow" to their backyard, we avoid these guardrails to keep the relationship to the backyard approachable and expansive. It is also worth noting a 30” deck height triggers the need for a building permit. For this reason, many DIY homeowners find themselves arranging their terracing around this rule.
The Maximal Solution
Alternatively, there are certainly many circumstances where a client has a great view and a lot of downsloping real estate they would like to have integrated into the living experience of the house, and this brings us to the more ambitious approach to backyard design that usually merits our services.
It will come as no surprise that detailing and building a strong code-compliant guardrail that is also of little impediment to your view is as much an art as it is a science. Transparency is not a characteristic of the most affordable guardrails. For this reason, and the previously stated goal of creating flow, we try to avoid introducing guardrails to backyard terraces. This begs the question: “If having a big hillside terrace implies a big dropoff, how can you avoid a guardrail?” Needless to say, if it comes down to a choice between having a comfortable terrace and guardrails, the guardrail is a frequent expedient solution. But there are ways to have a comfortable terrace without guardrails and this brings us to the solution of “planted retaining walls.”
If a client has steep downsloping backyard and great view, many elements come into play to take advantage of this. A pool is often an amenity that gets incorporated into this scenario but I will avoid this digression for the purpose of this article, and stick to terraces.
To avoid a guardrail we create two retaining walls instead of one. The lower retaining wall is placed less than 30" below the first terrace and is reserved exclusively for planting. Most juristictions will consider this an “open and obvious” hazard that negates the need for a guardrail. Obviously, you should always confirm these strategies with your authority-having-juristiction prior to making any big plans but it has been our experience that some version of this approach is usually permissable and a far more desirable living situation than the guardrail if it can be afforded.