The Crest House

Who doesn’t love a good story of ambition, adventure, love, and ultimately destruction?  Welcome to the Crest House atop Mt. Evans, what was once the highest building in the United States.

CrestHouse

This incredible organic, yet futuristic, building was erected between 1939 and 1941 and was the dream of German immigrant Gus Roehling.  Roehling cooked up the idea to build the Crest House for his girlfriend, later wife, after a visit to the top of Mt. Evans.  It took him a decade to secure private funding and permission from the Forest Service to develop a tourist center at the top of the mountain, but construction eventually began in the summer of 1939.  The building was designed by architect Edwin Francis, and upon completion in 1941 it housed a restaurant, a gift shop, restrooms and an observation deck overlooking the Front Range.  The restaurant was originally located in a semi-circular bay of faceted windows facing north, as seen in this excellent collection of historic photographs from the Denver Post.  The observation deck was atop the structure.

CrestHouse2

At 14,120 feet above sea level, the building site was one of the most rugged in the country.  Although it was accessible by the Mt. Evans Scenic Byway, completed in 1927, Roehling and his builders camped at the top of Mt. Evans during the summer construction seasons.  They did not have to look far for building materials, though; they took advantage of the natural light-gray and pink granite littering the summit of Mt. Evans for the building’s primary west façade with its four arches.  Both the exterior (first photo) and the interior (seen above) were built with local granite.  Here is a detail of some of the gray and pink granite found near the Crest House.

MtEvansgranite

The rest of the structure was erected using poured-in-place concrete.  The concrete is gray with a subtle pinkish hue, which was probably pigmented with crushed pink granite found near the building site.

CrestHousedetail

In 1979, a gas leak and explosion caused the building to burn.  If you look closely, you can still see bits of charred wood embedded in the concrete in the photo above.  In the early 1990s, the Crest House was stabilized but the roof and windows were never rebuilt.  Today, visitors can walk through the ruin to admire the architecture, as well as the views from the former restaurant.

MtEvansview

Textured Concrete at the Clyfford Still Museum

Although there are numerous historic masonry buildings in Denver, the city also has a good amount of unique, contemporary masonry structures.  One such building is the Clyfford Still Museum with its textured concrete façades.  The Still Museum was designed by Allied Works Architecture and built between 2009 and 2011.  One of the many cultural sites in the Golden Triangle Museum District, the Still Museum houses the collection of artist Clyfford Still.

StillMuseum

The contemporary design of the Still Museum is elegant and stately, but I am most fascinated by the textured concrete of the exterior façades.  According to several news reports about the opening of the museum, the textured-concrete skin was designed by architect Brad Cloepfil with numerous installation mockups by contractor Saunders Construction, Inc. and a custom concrete formulation developed by the Martin Marietta Corp.

StillMuseumdetail2

The north, west and south façades are clad with this textured concrete, which was cast in place using wooden formwork.  In the photo below, you can see the wood grain of the formwork on the soffit of the overhang, which imparts a nice organic texture.  The formwork at the soffit was also installed at a diagonal to offset the vertical stripes of the façades.

StillMuseumdetail1

To create the vertical texture on the façades, the contractor constructed wood formwork fins.  According to the Architectural Record: “The contractor created the fins by beveling the sides of some of the formwork boards to leave gaps; when the boards were pulled off, parts of the fins’ outside edges broke off to produce a jagged surface. The fins’ irregularity is an essential part of their character.”  You can see the irregular corduroy pattern of the textured concrete in the photo below.  It almost looks like a cascade of water running down the side of the building.

StillMuseumdetail3

As to the composition of the concrete, a case-study [PDF] from the Sika Corporation indicates that the concrete was custom blended from sources in Wyoming and Texas mixed with coarse and fine aggregate.  There is a prevalence of pink aggregate in the Denver area due to our proximity to the pink and gray granite of the Rocky Mountains, but the design team wanted the concrete skin to be a more neutral yellowish gray color.  Therefore, they selected aggregate that contained no pink granite.

The concrete was poured over the course of several months in varying temperatures and humidity levels, so the contractor had to pay close attention to the consistency of the concrete, its color (which can change as more or less water is added to the mix), and how fast the concrete set up.  As a result, several admixtures were included in the concrete mix to account for temperature, humidity, and varying set times of the concrete. [Update: I was asked about admixtures. Admixtures are chemicals or additives mixed into concrete that are used to improve the concrete’s strength or hardness, the speed at which it hardens, or the temperature at which it hardens, amongst other things.]

Although I have not yet been inside the Still Museum, I hear that that the architects made extensive use of textured concrete throughout the building.  The Still Museum website has some excellent photographs of the interior galleries and ceilings, which look amazing.