Casa Osa

Casa Osa

OBRA Architects
CerroOsa, Osa Peninsula, Costa Rica
Project Year
Private Houses
Product Spec Sheet
RoleBrandsProducts Used
ManufacturersLouis Poulsen
SupplierScofield Systems

Casa Osa

OBRA Architects as Architects

REMOTE AND UNPLUGGED This is the vacation home for an American doctor, his wife and daughter located atop a hill in the remote rainforest of the Osa Peninsula of Costa Rica. The site is located in the center of the peninsula with distant views of the GolfoDulce to the East and the Pacific Ocean to the West. From a very young age, the doctor has been fascinated by wilderness, and since he was old enough to travel by himself, he spent much time in the wild, visiting the Amazon, Africa, Belize, and other distant forests. The house is for him the realization of a long held project of a life in the proximity of exuberant nature.

Located in a 98 hectare lot of virgin forest, the house occupies a small hill that was formally cultivated as a mango farm, the only portion of the land which had been “civilized” in any way, thus offering a simple solution for choice of site without the need for clearing of trees.

An architectural memory of Frank Lloyd Wright saying that a house should never occupy the top of a hill, provided early inspiration for the project, but because Wright never specified how far up or down the hill the house should be located, the house is divided in four different wings that, connected with covered walkways, colonize the entire south side of the hill, leaving gaps between them for views of the surrounding forest to flow through, as do the monkeys, toucans and scarlet macaws.

SILENT INVISIBLE GEOMETRIES Stretching from entry of the property at the top of the hill down to the very edge of the bush at bottom, the different wings orient themselves according to the contours rotating in plan in relationship to one and other as they descend and privileging with their discrete axes of symmetry multiple points of fugue that structure the views of the forest around with silent invisible geometries. Organized this way, the sequence of arrival takes place descending the hill through the house itself, alternating between the stasis of the rooms articulated as simple boxes open to the benign weather on all sides with traditional double-sloped roofs and the connecting stepped ramps protected by a more complex triangulated surface. The house proposes as intimate as possible a collaboration with nature, defining the space as it often does as a sequence of descending gaps opening in different directions.

The house is split into five discrete pavilions, four of which are then interconnected with a covered step-ramp. The first pavilion near the entry is used as garage and storage for the batteries that accumulate the energy harvested by a solar panel located nearby. The next one contains the family’s bedrooms and a small vestibule open to the elements that serves as entry to the descending stepped-ramp that strings together the house, after the bedrooms is the dining room and kitchen pavilion and then the guest room, the last one, near the bottom of the hill, serves as living room. Two low walls, one connecting the dining room with the living room and the other the family bedrooms with the guest bedroom define two enclosed gardens, which serve as intermediate spaces between the forest and the rooms of the house, and provide the opportunity, when the light dies out in the evenings, to spend time outside without fear of the poisonous snakes which are abundant in this forest but naturally dislike the climbing of walls.

The arrangement proposes a controlled but unstable tension between the house as an object and the space of the forest as its site. It cannot be understood as a freestanding element surrounded by leftover land, nor as a boundary-like architectural arrangement encircling a courtyard, and thus gives neither primacy to object nor space. The house retains the integrity of the single architectural volume when seen from the outside, as the pavilions overlap in depth flattening the perception of the spaces lying between them, but as soon as we enter the house, effectively opening up vistas of the forest and the sky between the pavilions, that integrity is questioned and it becomes hard to decide if we are surrounded by one structure or by many.

The different pavilions are deployed on the side of the hill without regard for a favored orientation, and taking advantage of the relative height of the site, looks out over the treetops in different directions pointing towards the GolfoDulce to the East and South and towards the Pacific Ocean to the West.

Although the house embodies the desire of a family for a closeness with the forest, the house was also designed for the forest itself, conceived as it was with a minimum continuous footprint on the land and introducing a buffered network of intermediate spaces around and through the house, a “zone of controlled intrusion” so to speak that aims to allow a measure of intimacy without conflict between animals, plants and people.

With those goals in mind, house was designed to achieve the following five main points: 1. A desire for a measured and respectful proximity to the forest. 2. The definition of the spaces of the house in accordance with a weather of warm pleasant temperatures year round, protection from the unforgiving sunshine in the “summer” and from the seemingly endless rain storms during the “winter.” 3. Incorporation of the advantages of the hillside topography to have the house approach different corners of the forest and partake in their unique character of place and also, more subtlety, generate a psychological map of the houses “interiors” with intuitions of Up, Down, Gulf-Side, Ocean-Side, etc. 4. Developing an open architectural plan that encircles and frames portions of the landscape while allowing winged wildlife to literally traverse the house in all directions. 5. The use of a method of construction flexible enough to create the complex roof forms suggested by the demands of the plan descending down the side of the hill in accord with the topography, and yet simple enough to be deployed in a remote location with the resources of local labor accustomed to very specific and narrow manual modes of construction.

CONSTRUCTION: SIMPLE INGENUITY Due to its remote location as well as its extremely tight budget, the house is built with local well-known materials the Costa Rican builders are well acquainted with: walls are white stuccoed CMU with reinforced concrete structure, floors are polished concrete and ceilings and fenestration are wood from locally harvested already-dead trees. The roof in painted corrugated metal is structured with composite metal beams configured out of “C” channels connected with steel plate brackets bent on site, a system that allows a complexity of folding form easy to achieve on a site eight hours away from the nearest shop or hardware store.

The house encloses two walled gardens as it descends the slope. These are defined by low walls connecting the ends of alternating wings. Providing transition between “interior” and exterior, the walled gardens are outdoor places that can safely be used in the evenings when deadly poisonous snakes come out of the forest to freely roam about.

GENTLE YET RELIANT ON NATURE Like many houses in the Peninsula Osa, the house collects power from an array of photovoltaic panels. Water is harvested on the roofs and connected in a cistern and supplemented if necessary with water from a nearby stream that is pumped up the hill with a small electric pump. Heating here is unnecessary and cooling is provided by a few ceiling fans.

STRUCTURAL SYSTEM Reinforced concrete frame, reinforced CMU masonry

Exterior finishing: cementitious stucco painted white [roof]: exposed wood and steel-frame roof with painted corrugated steel

Interior finishing: cementitious stucco painted white, polished concrete flooring

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