CONCEPT

The Conservatory House near Varna is a place for recreation, relaxed chat with friends and fellow musicians, and contemplation with nature. Local residential building code for rural areas required collateral agricultural use which was in line with the owner's desire for having a large conservatory for growing flowers and hosting small life music events. Steep, picturesque, but compromised site initially used as local sand quarry and illegal waste dump later presented a good design challenge. It pushed us to think about how to restore the original slope and rehabilitate the local ecology. Naturally the waste was cleaned up, the house was fit into the existing quarry pit and the conservatory was put on top of the living spaces for catching maximum sunlight and minimizing footprint. This approach allowed us to use the house as a retaining wall itself and restore the terrain around and even inside it. The typical for every glazed garden heat gains and losses were addressed carefully throughout the design. As a result the conservatory became the main functional, aesthetic and environmental feature of the house. It allows daylight to reach all levels of the house, balances the indoor climate by the thermal mass of its soil, freshens the air with flower aromas and is a favorite place for relaxation. In summer the house benefits from the conservatory's natural cross ventilation, while in the winter the residents enjoy its greenhouse effect. Opaque insulated walls to West and North avoid summer overheating and winter overcooling. Cooling and heating losses in extreme conditions are compensated by a clean exchange with earth via six closed loop geothermal probes connected to a heat pump and radiant floors. The glazed roof collects all rainwater for irrigation and features integrated solar collector for domestic hot water. Living spaces under the conservatory have minimal heat losses due to its insulating effect. Reinforced concrete structure is chosen because of its local popularity and affordability. It is designed with a central core and load-bearing facade frames without internal columns and shear walls. Diagonal, vertical and horizontal structural elements on the Southern and Eastern facades follow the stress lines and reveal the building's tectonics. Organized in this way, the house resembles a tree with a green crown (conservatory), trunk and branches (structure) and roots (geothermal probes) with the residence accommodated in symbiosis within it. Natural landscaping promotes local plant species and preserves local microclimate. Bio-active wastewater treatment unit turns waste into bio- compost and irrigation water. Clean agricultural produce grown on-site adds to the experience of the Conservatory House .

FEATURES AND PERFORMANCE

Location: Rural

Site: Steep, eastward sloping, former sand quarry.

Vistas: Forest to the East and South (main), distant lake views to the North (secondary), West blocked by slope.

Purpose: Single family house.

Functional scheme: Three levels with central stair and accessible elevator. Dining, kitchen, three bedrooms, three bathrooms, support spaces on lower level; living, library, office, master bedroom, master bathroom, support spaces on middle level; interior garden, bathroom, support spaces on upper level.

Structure: Cast in place reinforced concrete comprising stem-like central elevator core and facade load-bearing frames without intermediate columns. Diagonals, verticals and horizontals on the South and East facades follow the stress lines derived from the structural analysis of the building mass. Structure becomes major architectural feature, providing efficient load bearing and maximum transparency and flexibility in planning.

Sustainable performance: Large glazed interior garden (tree crown) planted with a variety of grasses, herbs and spices produces oxygen and useful biomass. It balances the climate and improves the air quality of the entire house. In summer natural cross-ventilation combined with evaporation from interior water fountain and rapid growth of plants dissipates solar heat gain and provides cooling effect to the residential spaces below. In winter the garden works as an insulating hat for the house by catching sun and tempering the air via its liquid-heated floor. All additional energy needed for heating and cooling the house in extreme conditions is supplied by heat exchange from the ground via six 100-meter deep closed loop geothermal probes (roots). In spring and autumn extracted from the ground temperature is sufficient to cover the occupational needs. In summer and winter the energy is further transformed by a highly efficient liquid-liquid heat pump and distributed to all levels via radiant floors. Solar vacuum tubes supply domestic hot water further reducing building's CO2 emissions. Inversed roof funnels rainwater to a collection tank for irrigation of the garden. Residential spaces are accommodated under the interior garden and benefit from the winter garden's insulating effect. All domestic wastewater is recycled on site through a 3-stage purification station producing bio-compost and gray water for the exterior landscaping. Sustainable performance of the building is complemented with energy efficient appliances and lighting.

Materiality: Experimental nature of the project mandated strict cost management. Locally available inexpensive materials like concrete, stone and pine wood were specified in order to afford other important performance systems like insulated glass envelope, geothermal heat exchanger and radiant floors. All construction work was performed with local labor minimizing cost and pollution from transportation.

Interiors: Furniture and lighting are integral to architecture and built locally, except for seating.

Landscaping: All existing trees are preserved and site surface is restored to its original condition. No alien species are introduced in order to allow re-growth and healing of local ecosystem facilitated by fertilization with bio-compost from a local farm. Purposeful avoidance of cultivation preserves local microclimate, greatly reduces water and energy consumption and eliminates capital and maintenance costs of landscaping.

The formulation of the Home Tree concept and its realization indicate the need and show the possibility of building sensible contemporary architecture using local forces and means. We believe that the idea of developing nature-tolerant architecture will gain more supporters among architects and investors with the current development of affordable sustainable technologies.

Site area: 26 000 m2 (260 000 sf)

Building footprint: 260 m2 (2600 sf) (equals to 1% of site)

Total building area: 780 m2 (7800 sf)

Budget: to be released at a later date

Design: 2006-2010

Construction: 2007-2010

Status: built

ABOUT US

Ignatov Architects is a mobile architectural practice interested in finding inventive and effective solutions . The firm provides complete architectural services from site analysis to design and construction administration . We believe that meaningful architecture must be well-thought and specific to its purpose, location and users .
Currently Ignatov Architects work s on a couple experimental residential projects in Eastern Europe.

The company was established by Mr. Boris Ignatov in 2004 in New York and has offices in Manhattan and Varna, Bulgaria. Mr. Ignatov holds Master degrees in architecture from Columbia University in New York (2006) and Sofia University of Architecture (1995). He has worked for several large architectural firms including "Perkins + Will Architects" and is a licensed architect in the state of New York and Bulgaria .

CONTACTS:

e-mail: bignatov@bignatov.com

website: www.bignatov.com

phone: +359 884 335 810