2 Oaks House is located near Sofia in a low-rise residential area on the outskirts of Mountain Vitosha, Bulgaria, this 475m2 house was designed by Ostrev Baylov Ignatov Architects to take advantage of the natural sun and shade elements of the 2 pre-existing large and very old oak trees. The home was to be an energy efficient design with an automated indoor climate comfort control system, and the idea of using the Oak trees to provide shade in the summer, less shade in the fall, and none in the winter fit well within the scope of the project’s focus on energy efficiency
While the back of 2 Oaks House folds around one of the Oak trees in a U-shape, the front of the home also presents a slight folding aesthetic in the 2nd volume, only in this case it is presented through creative license rather then through the preservation of a tree. The initial concept that involved bending the home around the Oak created the concept of the home’s exterior folding as though it where a sheet of paper and that visual is well represented in the various planes of the 2nd storey.
The side of the 2 Oaks House showcases neither the architectural folds nor the wrapping of the home around the Oak, instead, the lush greenery within the landscape takes centre stage with its lush organic formations both in the foreground as well as from behind the building. From this angle the home nestles quietly into the shade of the Oaks presenting a silhouette that works with rather then against the landscape that surrounds it.
The back of the home is where the magic takes place with the large expanses of glazings opening up to a terrace that wraps one of the Oak trees. Even the two decks on the 2nd storey take advantage of the Oak’s shade and visual beauty. The trees create a micro-climate within the property while at the same time creating a living element to the hard lines of the architecture. It is as though the home is a large irregular shaped boulder that the tree springs forth from, reaching to the sky and sheltering the rock beneath it as it does so.
The preservation of the two Oak trees was of the utmost importance and by doing so the trees give thanks by helping with the thermal balance of the home. The Oaks have taken the role of nature’s protector, shading the large expanses of glazings from the summer’s heat, and by doing so contributing to the geothermal cooling heat pump system which removes excess heat from the home and circulates it down into the ground where it can be pumped back up during the cold months of winter. In winter the Oaks continue to play a role with their now leafless branches allowing the winter sun to flood through the bare canopy, through the glazings and into the home itself where the sun’s rays can then charge the thermal mass in the floor slabs.
The front of the home also has a deck that runs the length of the home. A large sliding glass door just in front of the dining zone offers access to this deck and a long fence creates privacy from curious eyes.
The entry is just around the corner from the private front yard deck and 3 large slabs of concrete access it, each slightly higher then the previous. Each small riser within these slabs is lit by a line of LEDs for safety while a row of pots also flood the wood siding as though directing the way to the front door.
The main level is the social volume with the entry leading to a small foyer also accessed from the two car garage on the left. On the right is a stairwell that leads to the second volume and straight ahead is the kitchen, dining and living zones in order as they wrap around the Oak tree terrace.
The social zone appears to be one large open space, but the kitchen is actually closed off from the dining and living zones with frameless glass panels that slide open or shut and while it can be closed off from the noise of the home, it is always visually present with its walls of glazings.
The trunk of the Oak tree within the terrace creates a living sculpture within the surrounds of this contemporary home and while during the cold months it is enjoyed through the walls of glazings, in the warmer months the walls of glazings can be opened up for a true indoor/outdoor lifestyle that brings an immediate connectivity to the visceral form of the Oak trunk.
The upper volume of the home is the private zone with two bedrooms and a bathroom, a Master Suite and a small office. This level also opens up to the Oak trees through walls of openable glazings that lead to two decks, one off of the Master Suite and one accessible by the rest of the rooms.
The bed in the Master Suite looks directly out onto the void between the two upper decks and here a TV is mounted centrally with the tree trunk. Access to the right deck is just around the corner from the green glass wall (which I love) and behind the green glass wall is the large walk in closet.
The upper decks are clad in wood with tempered glass rails to create the feel of being within the tree itself.
2 Oaks House is designed to be energy efficient and has a low temperature floor heating/cooling system with a geothermal heat pump deep boreholes). The home has triple gas filled glazings (Uw-1W/m2K), 20-16cm and it has been filled with thick glass-wool thermal insulation within the walls. There is also a controlled ventilation system that has a high level of heat recovery. The complete system is controlled via a fully automated and programmable system that not only allows the user to manage it from all areas within the home as well as from a distance, but also collects the daily data formulating statistics from one day, month or year to the next..
Ostrev Baylov Ignatov Architects
Photography by Alumina Elit, and Georgi Ivanov