Bade-Württemberg, Germany

Category:            Sustainable Houses
Year:                2026
Architects:          Atelier H2A, Mona Bayr 
Lead Architect:      Mona Bayr 
Client:              Private
Photographers:       Tom Philippi

Design Concept and Urban Quality: This multi-story timber building redefines the intersection of urban density and ecological consistency. The project exemplifies the implementation of a sustainable bioeconomy based on mono-material principles, serving as a best-practice model for pollutant-free, solid wood construction. The compact building envelope accommodates eight barrier-free residential units distributed across four floors.

From an urban planning perspective, the object impresses with its clean architectural language and deliberate orientation: while the eastern facade addresses the urban context through spacious loggias, the western side opens up towards the adjacent palace grounds (castle garden), creating an atmospheric quality of living with scenic views of nature.

Materiality, Resources, and Circularity: The project radically pushes the boundaries of circular construction. The load-bearing structure consists of a glue-free, solid timber system utilizing spruce and Douglas fir sourced directly from the adjacent forest. The future return of the construction into the natural lifecycle is fully guaranteed by purely mechanical connections using wooden dowels. The complete omission of insulation materials is made possible by the 42 cm thick dowel-laminated timber walls (Dübelholz).

The facade also breaks conventional standards: to avoid the use of fire protection boards—despite falling under Building Class 4 (GK4)—a non-ventilated construction made of dowelled Douglas fir planks was developed. This consistency extends to the interior fit-out: a solid beechwood heated screed from the local forest replaces conventional wet screeds, integrating the underfloor heating into a fully deconstructable system.

Low-Tech Approach and Energy Performance: The building pursues a “Simple Building” (Einfach Bauen) strategy. The mono-material composition of the exterior walls substitutes complex multi-layer assemblies with structural clarity, maximizing hygrothermal and structural durability. The moisture-regulating properties of the solid wood ensure a healthy indoor climate without the need for mechanical ventilation systems.

Passive Energy Measures: Above-average ceiling heights allow for larger window-to-wall ratios, enabling daylight to penetrate deep into the floor plans and minimizing the need for artificial lighting. The reduction of technical complexity minimizes maintenance costs and fosters long-term economic sustainability throughout the entire building lifecycle.

Quality of Living and Social Appropriateness: The floor plan typology is based on efficient, mirrored structures that offer high flexibility for diverse lifestyles. Every residential unit is barrier-free and accessible via an elevator, whose shaft features a double-wall construction to meet strict acoustic insulation requirements.

The living quality is enhanced by the tactile experience of the untreated timber and the generous loggias, which function as extended outdoor living spaces. Community-building aspects are promoted through a shared external staircase and integrated outdoor communal areas.

Degree of Innovation: The innovation lies in its radical regionality and technological simplification. The project proves that ecological construction utilizing locally available resources, short transport routes (local sawmill and regional timber prefabrication), and zero composite materials can be realized economically and with high architectural sophistication within Building Class 4 (GK4). It thus serves as a replicable blueprint for the affordable, pollutant-free housing of the future.

The facade also breaks conventional standards: to avoid the use of fire protection boards—despite falling under Building Class 4 (GK4)—a non-ventilated construction made of dowelled Douglas fir planks was developed. This consistency extends to the interior fit-out: a solid beechwood heated screed from the local forest replaces conventional wet screeds, integrating the underfloor heating into a fully deconstructable system.

Low-Tech Approach and Energy Performance: The building pursues a “Simple Building” (Einfach Bauen) strategy. The mono-material composition of the exterior walls substitutes complex multi-layer assemblies with structural clarity, maximizing hygrothermal and structural durability. The moisture-regulating properties of the solid wood ensure a healthy indoor climate without the need for mechanical ventilation systems.

Passive Energy Measures: Above-average ceiling heights allow for larger window-to-wall ratios, enabling daylight to penetrate deep into the floor plans and minimizing the need for artificial lighting. The reduction of technical complexity minimizes maintenance costs and fosters long-term economic sustainability throughout the entire building lifecycle.

Quality of Living and Social Appropriateness: The floor plan typology is based on efficient, mirrored structures that offer high flexibility for diverse lifestyles. Every residential unit is barrier-free and accessible via an elevator, whose shaft features a double-wall construction to meet strict acoustic insulation requirements.

The living quality is enhanced by the tactile experience of the untreated timber and the generous loggias, which function as extended outdoor living spaces. Community-building aspects are promoted through a shared external staircase and integrated outdoor communal areas.

Degree of Innovation: The innovation lies in its radical regionality and technological simplification. The project proves that ecological construction utilizing locally available resources, short transport routes (local sawmill and regional timber prefabrication), and zero composite materials can be realized economically and with high architectural sophistication within Building Class 4 (GK4). It thus serves as a replicable blueprint for the affordable, pollutant-free housing of the future.