Conjé is an experienced professional who creatively designs, remodels, retrofits, repairs, and recycles. She is passionate about circular building and believes it can simplify the process and reduce costs. “We must find more ways to save money, such as recycling or omitting certain elements – less is more,” she emphasizes. “However, this takes more time during the design stage and when explaining implementation.”

With her small planning office and a large network of specialist engineers, restorers, and regional craftsmen who know how to work with old buildings, Conjé aims to breathe new life into existing buildings. “I inspire my clients to be creative with what already exists. I encourage them to retrofit it, expand it, rethink it, and see the building in a new light.”

Stefanie Conjé is an experienced Baubiologin IBN, architect, and interior designer. With great love and dedication, she breathes new life into old buildings by finding creative ways to communicate, design, renovate, retrofit, repair, and recycle. She runs a Building Biology Consulting Office IBN out of her architectural office in Werder, near Potsdam.

1 The house on the Havel River before the complete renovation. The garage on the left still has a pent roof. Four additions have already been demolished to varying degrees.
2 Stefanie Conjé took the risk of using secondhand load-bearing building components for her private home. The raised window sills are visible in the background.
3 There is plenty of evening sun on the new terrace. The garage now has a flat roof, and the house has new windows and shutters.
4 A new picture window in the open kitchen offers a view of the sunset.

This is also a major issue under building regulations. Therefore, Architects for Future (A4F) created their “Model (Re)Building Code.” In 2023, the Working Group on Building Codes of the Federal Chamber of Architects (BAK) submitted a concrete proposal for a new, nationwide model building code. The goal is to harmonize the building codes of the federal states so that “the preservation of existing buildings is promoted in the spirit of the sustainable use of natural and existing resources.” “I think that’s great,” Conjé says enthusiastically. “Preserving old buildings is absolutely the right thing to do. But you also have to allow for the recycling of building materials without major bureaucratic hurdles. Unfortunately, building law isn’t quite there yet.”

She has worked with a large dismantling and demolition company for years to salvage and reuse building materials. “They send me photos when they find something great,” she says. “That’s how I get steel beams, old floorboards, front doors, door handles, and roof walkways. I then have the items refurbished and reworked.” She also knows a few suppliers who offer used building materials. For example, she likes to stop by Historische Bauelemente Marwitz, which is part of the Historische Baustoffe network (see LINKS below). (Tip from the IBN editorial team: “Building Material Recycling – Selling Instead of Throwing Away!”) “I’ve become something of a hoarder, collecting materials for our other projects,” she says with a laugh. In her garden lies an Art Nouveau railing with forged floral bands and blossoms that the historic preservation officer approved for installation elsewhere. She was once given large paneled doors as a gift, and now they are waiting in the basement for their second life.

Sleeping beauty

When Conjé found a listing for an 1892 house in a picturesque location on the Havel River, she was thrilled. Although the house had GDR-era additions, as well as outdated heating, plumbing, and electrical wiring, not to mention 40-year-old bathrooms and a tiled stove, the shell – a double-shell masonry wall made of regional brick – was in excellent condition. “It was a stroke of luck to be able to buy it,” she recalls. “We wanted to restore it to its original condition. That was important to the previous owners and makes the neighbors happy.”

Preserving the patina

The goal was to work with what was already there, preserve the patina, and repair any structural damage. “I wanted to keep it simple and use the house and its materials to tell stories,” Conjé emphasizes. She demolished or partially dismantled the vestibule, the “Trabi” garage (named after the iconic East German car), the garbage room, and the lookout tower – all poor-quality additions from the GDR era. Where the garage once stood, complete with a pitched asbestos roof, there is now a large terrace bathed in evening sunlight. The lookout tower has been replaced with a sunroom featuring a sustainable wooden frame. The new windows are built according to historical models and have narrow wooden frames and mullions that provide a better view. The addition of three large windows and a French door increases the amount of natural light and opens up the view of the evening sun and water. To create more harmonious historical proportions, the window sills facing the street were raised slightly. Now, all the windows are gracefully framed by new folding shutters instead of old roller shutters.

5 The newly added sunroom features slender wooden posts and Danish windows with narrow profiles that open outward.
6 The studio has a new bathroom and an open view of the wood fiber–insulated roof.
7 Vintage style: found, gifted, used, or discovered and then transformed. Upcycling at its finest!

Recycling of building components and materials

In the spirit of sustainability, Conjé passed on all the old windows. Interested parties just had to remove and pick them up. She gave her fairly new, soundproof vinyl windows to the electrician. Even the simple wooden windows from the GDR era were repurposed to build a greenhouse. The only unwanted item was the folding rubber door.

The floors were preserved almost entirely. Once several layers of flooring were stripped away, unpolished plank floors were revealed underneath. They were sanded and oiled. On the upper floor, the floors were oxblood red and heavily scratched. However, the painter touched them up just enough to let their history show through.

The steel beams above the enlarged doorways are recycled and have been evaluated by a structural engineer. “I can’t do that for clients because then I’d be liable,” Conjé points out. “The recycled beams are no longer approved by building authorities.”

The interior doors on the lower floor were salvaged from another old building. The carpenter built new door frames. “It was expensive, but they look really nice,” Stefanie Conjé says happily. All of the outdoor railings, totaling 18 m (59 ft) – were also reused. This saved quite a bit on material costs.

Energy and building biology

The new heating insert for the tiled stove meets current emissions standards and can heat the entire house. You can also see the fire through a small glass pane. The new baseboard heating system complements the stove and is ideal for regulating the temperature of the walls in this old building. The electrical installations are new as well. The attic and roof have since been insulated. After doubling up the rafters, wood fiber insulation was blown into the spaces between them. Now, they provide excellent protection against cold in winter, the heat in summer, and noise.

Thanks to the use of building biology–approved finishing materials, the indoor climate is comfortable. The existing interior lime plaster was supplemented with more lime plaster. The wood surfaces were treated with a permeable oil finish. The bedrooms were equipped with a demand switch. The interior designer furnished the rooms in an authentic vintage style. All the furniture found on the street, at construction sites, along the roadside, at flea markets, in classified ads, or received as gifts, was upcycled and modified to fit. Thus, the house tells many stories. It is currently being rented to vacationers until the homeowner and her husband move in, as it is her “absolute dream home.”