Architecture studio Kallos Turin paired the cubic facade of this poured concrete Athens house with a sloping internal staircase to avoid creating a "rigid" home.

Named Art House, the four-storey dwelling is located on a leafy hillside in Filothei – an Athenian suburb developed in the 1920s as a greener antidote to the densely built-up city centre.

London- and San Francisco-based studio Kallos Turin sought to create a large volume to house its residents' vast art collection while adhering to the natural landscape.

"Local restrictions designed to preserve greenery in the property's neighbourhood resulted in limitations to the overall footprint and the floor plan," said studio co-founders Stephania Kallos and Abigail Turin.

"We happily rose to the challenge, doubling down on the idea of a dense volume that emerged from a garden designed to be as concentrated and powerful as the built volume itself," they told Dezeen.

The garage and the floor directly above it were built underground but carved with large lightwells, as the property was permitted to have subterranean levels as long as they did not extend beyond the boundaries of the exterior walls.

Visitors approach the cube-like house at the street level and enter via a curved concrete wall. A stepped path winds through the site's planted landscape and up the hill to a bronze and brass perforated front door.

"An aspect of the project that feels emblematic of its style is the way that the house and garden wrestle for power on the site," said Kallos and Turin.

Inside, the home is defined by a meandering cantilevered staircase that spans all four storeys, designed to be a direct contrast to the largely cubic facade.

"We did not want the experience of the home to feel rigid," explained the architects.

"We loved the idea that the way you move through the volume could be a sinuous line of travel and that this line would then impact the shape of the concrete," they added.

The top floor holds the main living area and a kitchen finished in stainless steel, with floor-to-ceiling glazing that opens onto the garden patio, complete with a dining table and a built-in barbeque.

Accessed via the sloping central staircase, the second floor down is a gallery-style space dedicated to the majority of the owners' art collection, including colourful paintings that hang from the concrete walls.

The floor below this level contains the main suite, a guest room and a home gym, and provides another display area for more artwork.

In addition to the home's four storeys, there is also a rooftop swimming pool.

Accessed via an external concrete staircase, the rooftop features sweeping views of Athens and a partial green roof.

When constructing Art House, Kallos Turin took various measures to respond to the harsh local climate.

The home benefits from the "natural sunshade" of its hillside location, while it was also positioned so that its southwest-facing spaces are exposed to maximum sunlight during the cooler winter months.

Roof overhangs and blinds were fitted to the north-facing facades to reduce heat gain, while large windows and sliding doors optimise cross ventilation throughout the home.

"The property's architecture serves as a natural way to limit energy consumption by reducing the need for heating and cooling systems," explained the architects.

"Additionally, the green roof reduces the Urban Heat Island effect. These cooling effects have eliminated the need for air-conditioning altogether, despite temperatures of over 30 degrees for several months a year," they added.

The studio chose a mixture of dark blues, camel and black metal for the overall interior palette to allow the colours and materials of the furniture to "hold their own without screaming for attention," explained Kallos and Turin.

Pieces range from Gaetano Pesce chairs to an Eros table by the late architect Angelo Mangiarotti, while the bathroom was finished in large blocks of veiny light-green marble.

"When creating the interiors, we viewed the house's concrete shell as a 'neutral' base – the equivalent of white walls in an art gallery," concluded the architects.

Elsewhere in Greece, Block722 studio arranged an earthy-toned holiday home down another mountainside in Crete. In Santorini, local studio Kapsimalis Architects created a holiday home informed by a large piece of volcanic rock.

The photography is by Giorgos Sfakaianakis unless stated otherwise and the video is courtesy of Kallos Turin.

Project credits:

Design architect and interiors: Kallos Turin
Local architect of record: Moustroufis Architects
Lighting designer: George Sexton Associates
Landscape designer: Doxiadis+
Project manager and contractor: Diolkos Group