critical regionalism – an experiential approach, Part Two

As an extension of the thoughts in Part One, I would like to talk about some of the possible architectural responses to local geology and climate discussed in the previous post.  What is of interest here is how these responses may combine to create a body of work that expresses a kind of regionalism without regard to specific building form or style.  Below are descriptions of the types of architectural responses that might be found in the Rocky Mountains and when synthesized in various combinations, may describe a kind of regionalist architecture.  I have included some photos from a house I designed a couple of years ago to possibly demonstrate the architectural response to a given condition.

Soil Conditions

point loads on posts and lintels

The seasonal expansion and contraction of our local soils and the ability to point load on granite might drive a design to be more expressive of post-and-lintel type construction than continuous wall construction as is typical.  This is obviously very dependent on exact, specific soil conditions and may not express itself in all projects.

Solar gain

Because of the intensity of the sun and general aridity of the mountain West, the roof is often used more as a shading device than a rain protector.  This results in large overhangs which create a kind of interstitial space between the interiority of the building and the purely uncovered exterior space of the landscape.  This middle space of covered outdoor space may also become more formalized as covered terraces or balconies.

Another resultant of the intense solar gain is its effect on building materials.  Untreated wood, left exposed for even a short period, will quickly splinter and decay.  Even when treated, the UV rays of the sun quickly breakdown most stains and paints, making wood a relatively short-lived building material especially when compared to the centuries-old timbers and siding of East Coast houses.

exterior "room", partially roofed

Lastly, the infrequency of rain also coincides with an abundance of sunny days, around 300 or so per year.  Given the general altitude of much of the mountain west, that means that even on a freezing day, a pleasant afternoon can be spent on an outside terrace in direct sunlight.  So, like many California modernist houses, this creates the ability to live outside for much of the year, although this tends to be more for winter afternoons and summer mornings rather than purely seasonally determined.

Windy, dry conditions

very limited use of exposed wood (stone walls, metal roof)

The combination of occasionally fierce winds and frequently very low humidity creates many days of red-flag fire danger days.  These conditions, combined with the intense solar gain, quickly deteriorates wood, making it even more susceptible to even the smallest falling ember.  This may make a strong case for eliminating exposed wood from building exteriors and using much more fire-resistant materials like stone and metals.  Abundant native stone, both granites and sandstones, would reinforce this regional material usage preference.

Aridity

xeriscaping right up to the face of the building

As a possible corollary to the windy, dry conditions listed above is the extreme aridity experienced on the east side of the Continental Divide.  Most of our streams and rivers are charged with snow melt, not rainfall, and the storage of water and its conservation has written much of the history of Western land use.  As differentiated from the damp Midwest or East Coast, the lawns of typical houses are irrigated and with growing awareness of the scarcity of water resources, xeriscaping has become the preferred method for treating the land in the spaces between buildings.  These xeriscaped areas are marked not by low, gound-hugging grasses like prototypical “lawns”, but are combinations of native bushes and tall grasses.  Because of this variety and size of plantings, a building in the mountain West does not sit on a generic, de-natured green tableau but is a built moment in a continuous landscape of native plants.  The building does not sit within its own domesticated space of green lawn, but either interfaces directly with “wilderness” or must use other architectural devices to establish this domesticated zone of semi-public, semi-private space.

I am sure there are a lot of other buildings in the mountain West that demonstrate the same or similar responses to these conditions.  In a future post I will try to find classes of other examples that span many different architectural styles but have in common these traits, including vernacular architectures.

critical regionalism – an experiential approach, Part One

I have written a number of times about critical regionalism and the surprising lack of a kind of regional identity in the architecture of the Rocky Mountains.  Most of this thought has focused on Kenneth Frampton’s seven points as expressed in his famous essay and a conception of regional architectures on largely formal and material terms.  I would like here to examine some thoughts on a different kind of regionalist expression, one based on a phenomenological or experiential response rather than the usual form-based or academic anthropological regionalism.

traditional Ticino house and Mario Botta house - formal response to vernacular

To be clear, there are some kinds of local vernacular architecture from which a form-based critical regionalism might take some clues.  In the southern Rockies there is the very clear and frankly painfully codified adobe typologies of “Southwest style” architectures.  Here in the central Rockies there are large collections of metal-clad mining buildings and some timber structures that can be identified as unique to this region in terms of both building form and material usage.  However, I think a phenomenological approach to thinking about a critical regionalism may have a more fruitful outcome than form-based approaches and the unique human responses to the characteristics of this region’s high desert climate have generated a stronger and more complete body of regionally unique architectural expressions than any collection of formal attributes from already existing buildings.

To that end, here are some thoughts and statistics on local climate and geology:

Earth – here in the foothills of the Rocky Mountains we are blessed and cursed with two diametrically opposed subsoil conditions that greatly effect the modes of foundation construction.  On the one hand there are large expanses of granite above and immediately below the surface.  At some locations this allows buildings to be directly supported on the rock itself negating the necessity for standard concrete foundations and footings.  However, in opposition to this kind of immovable earth, we also have large areas of expansive soils.  These are clay-like subsurface soils that swell when wet, shrink when dry.  This kind of movement makes traditional concrete foundations on footings impossible, making drilled piers and associated grade beams the recommended practice in these areas.

Wind – even though we may be in the central United States, far from any ocean, gale force winds are not all uncommon along the Front Range.  Warm air sweeping up from the south rushes into low pressure zones along the mountains necessitating a standard wind pressure design assumption of 130 mile per hour.  These winds are relentless, tumbling outdoor furniture across the landscape, upending signs and anything else left outside during these Spring and Autumn wind seasons.

Fire – as has been made abundantly clear with the loss of 170 homes during the Fourmile Fire and evacuations of the recent Dome Fire here in Boulder, the extreme aridity of the Front Range makes ignition resistant construction an absolute necessity.  Daily humidity readings in the 20% range, coupled with the high winds as described above, creates the certainty for wildfire.  Human-sourced ignition is the most common cause of wildfires, but a significant number of conflagrations are also started from the dry lightning storms that afflict the region.

Water – what ties all of these climactic extremes may be the striking lack of water in the West once you move beyond the 100th meridian.  Boulder receives fourteen inches of precipitation per year, ten of that in form of snow falls.  From late April to some time in September the only rain that falls comes in brief afternoon storms that occassionally drop some rain.  Long, hot, dry days throughout the summer are marked by about 3o minutes of downpour which then dries as quickly as the clouds appeared and departed.  This pattern is most acute in late July and August but only contribute about 2.5 inches of rain total for a two month period.  By comparison, in my native Kentucky yearly precipitation runs to 44.5 inches and the two dry months of July and August combine for 7.7 inches of rain.

In an upcoming post I will talk about some of the architectural responses to these conditions and how those might combine to make a kind of regionalism that is not based on any notion of an architectural style.