HEDS Architects Night Song Bridge House has a deep resonance with its wooded site; - the corten steel façade is the color of red clay while its corrugations whisper the beat of nocturnal sounds.

Night Song Bridge House inhabits the treetops, is connected to nature, to the sky, and to the earth. It is a house that bridges a ravine, one where the facade is a music score of a hoot owl's night song; the house is connected to its site on a granular level.

The site is heavily sloped with a ravine running through the wooded property. It overlooks a valley and mountains beyond. The client wished to create a retreat in the woods that takes advantage of the views.

The site offered different building opportunities but a ravine suggested intriguing possibilities and the architect imagined a bridge house that would lift off from the hillside as the slope drops away.

The main "bridge" level spans the ravine to take up residence in the treetops. The lower level is of the earth, made of concrete that terraces with the sloping terrain. The upper level is clad in corten steel that rusts to the color of the local red clay. The house thus has two natures, one that inhabits the tree canopy and one embedded in the earth. Materials were selected to reinforce the deep resonance with the site.

The bridge is a long bar split in two with a connecting covered porch (a modern interpretation of the "dogtrot" vernacular). The main living spaces are at this entry level - the family room, kitchen and primary bedroom. Large expanses of glass embrace the view to look both up and down slope. A long skylight extends the length of the house -- the house is full of lever-changing light.

A perforated metal stair descends to a lower-level family room and children's bedrooms. The pool and concrete terraces touch ground here. Water appears to slip over the pool edge into the ravine below.

The corten metal ribbing, color of the local clay, is custom - night-time sound recordings were graphed and used to set up the cadence of the corrugation. Corten perforated metal compliments the corten panels - the raindrop pattern picks up on the nocturnal chorus.

In contrast to the lightness of the bridge cladding, the lower level is built of concrete. Its surface is a canvas animated by the dappled reflections of the pool.

A series of elements in the house (the master bath concrete tub and vanities, the two built-in fireplaces and breakfast table) have amorphous forms that recall the large boulders onsite. These elements both provide additional connections to the site while softening the rectilinear nature of the house.

The concept behind the house was to connect the home's family to nature in big and small ways - through the spaces - the planted roof terrace, the covered elevated porch, daylit rooms and the lower level terraces - through the materials - the lightness of the metal at the bridge and heaviness of concrete as it touches ground - and through the details - the corten steel the color of red clay that is in beat with the night song of a hoot owl.

The Night Song Bridge House leverages the fundamentals of passive solar home design:

Building massing facilitates cooling through natural ventilation -- The upper level is a "dogtrot" - a local southern vernacular building type whereby a breezeway is captured between two living spaces. Large sliding doors open to the dogtrot porch and operable windows within the interior adjacent spaces draw air currents through the living quarters. Automated roller screens transform the porch to a screened area, allowing the living area to partake of the outdoors when weather is temperate. These strategies reduce loads associated with cooling.

Envelope Design meets Passivhaus standards -- The house is super insulated with Passivhaus certified triple-pane windows, R-30+ walls and R-60+ roof. Sheathing is Huber ZIP system to address thermal bridging. Henry Blueskin supplements the ZIP weather protective barrier -- its self-healing membrane inhibits moisture infiltration due to fastener penetrations.

Heating and cooling is handled through geothermal packaged systems using high-efficiency water-to-water heat pumps with an EER raiting of 19.7.

The above strategies create an optimized envelope design.

Active energy systems enhance the passive solar design: A 12 KW photovoltaic system on the roof and geothermal significantly reduce electrical loads.

Vegetated green roof replaces lost habitat -- The roof is either covered with solar panels or a vegetated green roof. The green roof absorbs rainwater, releasing it slowly into the atmosphere. To the passing bird, the roof looks like home.