Urban infill development will be the significant future construction task as it creates usable spaces without further sealing and infrastructure expansions. A significant proportion of residential buildings date back to the 1950s-1970s and exhibit favorable conditions for infill development and, in particular, vertical expansion: regular structural typologies, often with building density reserves, and already serviced by infrastructure. Prefabricated solid wood construction is excellently suited for this task due to its short and dry construction process, low weight, and minimal disturbance to residents. However, the high diversity of timber construction, the lack of standards for building class 5, and company-specific execution guidelines lead to uncertainties in planning, costs, and implementation, thereby impeding industry growth.

The LoftConcept project aims to establish structural and building physics foundations for expanding existing buildings using solid wood construction. It also aims to develop an interdisciplinary parametric solid wood construction system for infill development in Austria and southern Germany. Digital models will ensure coherence between early design decisions and suitability for execution.

Invariant detail node constructions will be linked to dimensionally variable component constructions. The foundations for the automated calculation of performance indicators and building characteristics will be determined based on generic designs derived from existing analyses. Furthermore, foundations for future utilization and transfer to other target markets will be developed.

The project primarily contributes to theory formation through the development of standardized basic building blocks for complexity reduction and ease of application, parametrization, and derivation of performance characteristics of elements and connection details for residential use in infill development. Secondarily, pattern solutions for multi-story timber construction with approaches for typology, structural design, sound insulation, fire protection, thermal insulation, and life cycle assessment will be provided. This will promote timber construction and thus encourage the sustainable use of solid wood as a building material and carbon sink.

The industry and timber construction partners benefit from system solutions, input for system and product development, as well as digital models for planning, execution, and stakeholder support. The planning partners will acquire expertise in parametrization and standardization. The research partners benefit from collaboration, new research ideas, and the development of expertise in digital models and parametrization.