Twin Lake Residence

The Twin Lake home merges sustainable water treatment into an exquisitely detailed Modern renovation and landscape. The design respects and enhances the detailing of the California-Modern style home, while also pre-treating the rain runoff from all hardscape areas and half of the home’s roof. New terraces create indoor/outdoor living spaces that feel as if they have always been a part of the home. Innovative environmental features include a custom-designed and rapid-protoyped gutter cascade, a recirculating purifying water feature, a subterranean sand filter, and a wetland pre-treatment basin,

Completing the Indoor/Outdoor Living Space

The designers sought early on to respect and enhance the architecture of the home. California-Modern in style, the home had an open-plan interior that should have flowed out into the landscape to create indoor/outdoor spaces. However, when the home was completed in 1948, the landscape treatment was basic: stairway and lawn. The constructed design creates a landscape that both aesthetically and functionally completes the marriage of home and landscape. A series of stone terraces extend forward into the landscape to create outdoor living spaces. The surrounding limestone walls finish the composition of the house by stretching it horizontally and accentuating the vertical chimney at the center of the composition.

The indoor/outdoor transition is handled with unparalleled detail. New custom French windows open onto the terrace, creating a seamless transition. The floor of the terrace is exactly the same as that of the living room—a key feature of California Modern homes often overlooked in the Midwest. A new water feature converts an existing planter near the front door into an upper pool, and creates a new lower pool at the terrace level. A steel weir drops water into the lower pool in the shape of a circle. When it rains, a custom spout from the roof gutter above creates a tight, spiraling cascade that drops through the center of the circle. This seemingly impossible water movement was developed through hydrologic simulations and rapid prototyping of the gutter spout. The rectilinear alignment of the terrace, drawn from the existing lines of the home, is expressed without error in the placement of the walls, the joints in the paving, the custom-fabricated lighting inset under each stone step, and the custom-designed wood and metal seating and arbor.

Modern Sustainability

The recirculating water feature and gutter cascade are key aesthetic features of the design, but they serve another, more important purpose. The recirculating feature includes a UV treatment system to reduce algae buildup and reduce pathogens. At Twin Lake, because water from half the roof drops into the water feature through the gutter cascade, all this water is purified by moving through the recirculating system. Water then overflows from the feature into pipes under the terrace and enters a subterranean sand filter just beyond the edge of the terrace. Water falling on the terrace irrigates the planting beds—excess is piped to the sand filter. The water then moves into a new constructed wetland near the back of the home.

While the front yard is geometric and Modern, the rear yard has a wilder feel. The home sits astride a steep slope, and the basement floor is revealed on the back side of the home. In the back forest, water flows from the constructed wetland into a larger existing forested wetland at the lowest point of the yard. The linkage between front and back is made via a steel-and-gravel-box stairway that hovers above the slope to reduce erosion. The geometry here is more casual, encouraging a woodland stroll down onto a series of gravel pathways and seating areas.