**From Single Family to Duplex House by MWArchitekten

The project “From Single Family to Duplex House” by MWArchitekten transforms a 1960s single-family residence in Austria into a modern, energy-efficient duplex designed for multigenerational living. Rooted in sustainability, redensification, and adaptive reuse, the renovation prioritizes minimal intervention while significantly improving spatial quality and ecological performance.

Project Vision and Context

Responding to the client’s desire for a sustainable and future-proof property, MWArchitekten approached the project with a strong emphasis on resource efficiency and building reuse. Instead of demolishing the existing structure, the architects worked with the original fabric—maintaining its core while strategically expanding it into a functional two-family house.

This decision aligns with Austria’s growing interest in densifying existing residential neighborhoods, reducing land consumption, and enabling flexible family living models.

Sustainable Transformation & Redensification

The renovation integrates thermal upgrades, energy-efficient systems, and improved building performance. The 1960s structure—originally not designed for today’s ecological standards—was thoroughly retrofitted with enhanced insulation, airtight detailing, and modern building services.

By preserving as much of the existing structure as possible, the project reduces embodied carbon and supports circular construction practices, making it an environmentally responsible alternative to new construction.

Architectural Additions and Spatial Reorganization

To accommodate two households, MWArchitekten introduced an open staircase, creating a vertical connection that organizes circulation without compromising interior openness. The attic was expanded and restructured into a livable, well-lit floor, offering additional space for the second household.

Large windows and carefully placed openings bring natural light deep into the interior, improving comfort and reducing reliance on artificial lighting. The interior—defined by clean lines, warm materials, and efficient layouts—supports modern family lifestyles while maintaining the character of the original house.

Materiality and Craftsmanship

The project showcases the work of regional craftsmen, including:

• Künzler Joinery for woodwork
• Bechter Best for plumbing
• Phitsanu-Elektro for electrical systems
• Bader Bau as master builder Complementary elements by manufacturers such as Miele, Velux, and Bolichwerke contribute to a contemporary, durable, and functional residential environment.

Exterior Spaces and Access

Thoughtfully redesigned outdoor areas enhance both access and everyday living. These semi-private spaces serve as extensions of the indoor environment, supporting relaxation, play, and family gatherings. Their integration completes the renewed building volume, giving the duplex a cohesive presence within its neighborhood context.

A Model for Sustainable Residential Renewal

This project illustrates how adaptive reuse and careful densification can create high-quality, multigenerational housing without excessive resource consumption. MWArchitekten’s intervention demonstrates that past and present can coexist meaningfully—maintaining architectural heritage while adapting to contemporary needs.

All photographs are works of Dominic Kummer