Werner Völler, a renowned Frankfurt architect who contributed to major construction projects including the Commerzbank Tower and Exhibition Hall 3, is now dedicating his retirement years to historic preservation as a volunteer curator for the German Foundation for Monument Protection. During this Sunday's Day of Open Monuments, visitors will find him guiding tours through the opulent Villa Mumm on Kennedy Avenue in Frankfurt-Sachsenhausen, a magnificent building commissioned by the Mumm von Schwarzenstein champagne dynasty in the early 20th century.

For interviews, however, Völler prefers meeting in a more modest setting - the Steinhausen House in Frankfurt's Westend district, one of the city's smallest museums. This unassuming building near the university campus served as both home and studio for painter and graphic artist Wilhelm Steinhausen, who died in 1924. Today owned by the city of Frankfurt but operated by the private Steinhausen Foundation, the museum struggles with limited funding and would have been unable to complete its historically accurate renovation without support from the German Foundation for Monument Protection.

Since 2015, the foundation has funded several restoration projects at the site, most recently providing €20,000 in December. The 1885 rowhouse features a generously lit studio on the second floor that captivates Völler's imagination. "This was supposed to be an artists' colony," he explains. "This house is the only one that survived. You rarely find something like this elsewhere." He points to wall paintings in the stairwell that were carelessly painted over during 1980s renovations but have now been restored to their original appearance thanks to foundation funding.

The studio, with its large skylight and beautiful view of greenery, creates the impression that the painter has just set down his brush. "A building like this cannot be maintained with private funds alone," Völler observes. He notes that small monuments often stand in the shadow of grand castles and churches, making it difficult for them to secure funding - precisely the type of projects the German Foundation for Monument Protection prioritizes.

Born in Osnabrück in 1956 and currently living in Hanau, Völler first encountered historic preservation during his training as a mason and plasterer. He continued focusing on monument conservation during his architecture studies, though his 40-year professional career with prestigious firms like Hochtief and OFB Project Development primarily involved major new construction projects both domestically and internationally. His son Bastian followed in his footsteps, studying architecture with a complete focus on historic preservation and now operating his office in one of Büdingen's oldest buildings in the Wetterau region.

Since retiring five years ago, the senior Völler has returned to his passion for historic building preservation. For about a year, he has served as a local curator for Frankfurt, joining approximately 500 volunteer staff members of the German Foundation for Monument Protection, founded in 1985 and responsible for coordinating the annual Day of Open Monuments. Together with about 15 colleagues, he serves as the foundation's contact person in the Rhine-Main region, presenting funding approvals and inspecting potential projects worthy of support.

Recently, Völler and the local curatorium visited Schmitten in the Taunus mountains to examine the so-called Nadler House, the last remnant of a specialized craft. This half-timbered building once housed artisans who produced pins, hairpins, hooks, eyelets, and chains. While the municipality would like to preserve the structure, it remains in very poor condition and lacks funding for restoration. Völler hopes the foundation might be able to help.

Another project involves painter Steinhausen, who created large-format frescoes in several buildings. Preserved works include frescoes in the auditorium of Heinrich-von-Gagern Gymnasium in Frankfurt's Ostend district. "Many people walk past them without notice," Völler observes, aiming to bring these works back into public consciousness.

Völler maintains a pragmatic approach to historic preservation, considering economic factors as well. "I can understand any owner who has difficulties maintaining a building," he states. He believes not every structure needs preservation for future generations - exemplary specimens suffice. He illustrates this philosophy using the former Hochtief headquarters on Bockenheimer Landstraße in Frankfurt, a protected building designed by architect Egon Eiermann that was demolished 20 years ago to make way for new high-rises. Völler finds this acceptable since Eiermann designed similar buildings that remain preserved.

Regarding renovations, Völler avoids purist positions. "Not every train station is such an important monument that it cannot be redesigned," he argues, believing cities should have more decision-making freedom. Office buildings with ceiling heights of only 2.1 meters cannot meet today's requirements, and "monument protection is meaningless without practical use."

The architect considers many new Frankfurt buildings interchangeable and lacking potential to become monuments, wishing for more design guidelines from the city. He also believes not all high-rises need permanent preservation. However, regarding one building he knows particularly well and considers technically state-of-the-art, he remains convinced of its future value: "The Commerzbank will certainly be placed under monument protection someday." Unlike the 1997 skyscraper, a slightly newer high-rise has already made the monument list - the former railway headquarters in Gallus district, an example of concrete brutalism open for viewing during the Day of Open Monuments.

The year 2025 holds special significance for historic preservation, marking 50 years since the European Monument Protection Year initiated a transformation in handling historic building stock, and 40 years since the German Foundation for Monument Protection's establishment. Since 1993, the foundation has annually focused attention on cultural heritage through the Day of Open Monuments. This year's program, featuring approximately 8,000 events in 6,000 monuments across Germany on Sunday, September 14, operates under the theme "Valuable: Priceless or Irreplaceable?" addressing topics including materials, costs, and personal significance of monuments.