negative energy consumption house

One of the goals of eco-friendly construction is to create homes that not only use fewer resources than conventional homes, but to create those that actually produce more energy than they consume. The house, located in Kladnica, Bulgaria, was designed and built by Studio Apxe. The focus when designing the home was to make it as energy efficient as possible while minimizing its impact on the picturesque mountainous surroundings.

front exterior passive house
passive energy house

The home was built on a solid concrete foundation with concrete supporting supporting frames and garage roof, but the rest of the structure is lightweight steel and timber. Thanks to excellent insulation and sun protection, the home needs no cooling in the summer and uses very little heat in the winter. Solar panels on the roof and a biomass heating system contribute to the energy saving and production of the home.

kladnica bulgaria passive energy house
interior passive house apxe

A controlled mechanical ventilation system with heat recovery provides the home with fresh air in all seasons. Careful measures were taken to ensure the air-tightness of the home. This feature controls energy loss and qualifies the house as passive by keeping the energy consumption around 38 kWh per square meter annually, a figure that falls far below the 120 kWh per square meter requirement.

Construction of the home used as many locally-sourced materials as possible. Other energy saving methods, such as separating the garage and other colder spaces from the living spaces, are employed to further increase the single-story home’s eco-friendly rating.

“The challenge was to fit successfully the large scale one-story building in the green landscape without appearing foreign and superfluous there. We detached by their volumes and structure the garage and the cold service premises from the residential part. This solved many technological and energy problems with the external surface thermal bridges. The volume of the garage is fitted at street level, dug into the rock and the house is partially over it, standing broad.”

“The building was built with a lightweight ecological load bearing structure. Only the foundations, the supporting frames and the roof of the garage are made of reinforced concrete. Everything else is designed with a lightweight steel and timber structures. This lightens the weight of the structure and reduces the budget as well. Laminated wood beams and columns pergola with built-in sun protection form the appearance and the elements of the architectural envelope. The house is designed in accordance with the Passivhaus standard.”