Balcony glazing – Poppenrade
“Due to the extremely shallow balcony, the combination of a facade system and a thermally insulated bi-folding door was the perfect choice. The building’s thermal insulation level is shifted from inside the recessed balcony to the outside, without cutting back on the overall area of the balcony.“
Frank Oschetzki, foreman and architect

Expanding living space with balcony renovation

Standing tall over a long row of free-standing residential blocks, the high-rise apartment building Poppenrade 5 in the “Poppenrade” district of Kiel, northern Germany, characterises the residential area on the city's eastern shore. Built in the 1970s, the 202-flat settlement was initially considered a highly popular neighbourhood. However, as is so often the case, this perception changed with time. The outdated standard of energy and the consequent threat of apartment vacancy prompted the housing cooperative, Wohnungsbau-Genossenschaft Kiel-Ost eG, to undertake extensive energy renovation and modernisation measures. These culminated in the subsequent renovation of the high-rise Poppenrade 5 apartment building.

Poppenrade vorher

Boost residential value – avoid vacancies

The comprehensive renovation of the quarter began in 2013, with three construction phases designed to give the area a modern facelift. “In addition to the aesthetic and accessibility improvements to the residential block, our main focus was on energetic renovation for the facades and balconies,” says Norbert Hansen, Head of Technical Inventory Management for Kiel East. “First and foremost, we wanted to improve the quality of life for the residents of the outdated flats and balconies. This would also save us from having to deal with empty flats.” 
Architects’ bureau AX5, who were place in charge of the project, had to deal with a number of challenges, especially when it came to Poppenrade 5. Due in no small part to the thermal bridges in the balcony slabs, which protruded into the indoor living space, the architects and the co-operative came to the joint conclusion that it would be best to renovate the balconies in a way that provided more space but stopped short of removing them and losing their classic, open-air feel. 

Poppenrade Schnitt

Ingenious systems

With their ingenious balcony solutions, it soon became clear that Solarlux were the best partners for the job. The main benefit of the balcony system the architects chose was that it kept the recessed balconies the same size, which would not have been possible with a conventional renovation. The thermal insulation installed on every side takes up no extra space, whereas a similar solution in a thermally insulated composite system would have eaten up 20% of the area. Thanks to the bi-folding doors, the balconies have retained their character yet been transformed into fully fledged living spaces – the bi-folding door can either be kept closed or opened across the width of the balcony, depending on the weather. In addition to this, less space is required to open the bi-folding doors than for a conventional turn-and-tilt window. The system also boasts a number of ingenious design details. The frame has been designed specially to be fitted with waterproofing film and aluminium sheet cladding to allow a clean joint with the facade. At the same time, the built-in cleaning pins make it easy to clean the outside panes from the inside, so there is no need to pay for an expensive facade cleaning service. 

Poppenrade neu

Light and air

The bi-folding doors have also been incorporated into the flats’ ventilation concept: each of the 56 bi-folding doors is equipped with an 80-centimetre fan for optimum air circulation. Since the balustrades are now made of glass rather than reinforced concrete, the living space is now pleasant and bright. The frosted glass used in the lower section of the balustrade acts as a privacy screen for the balconies, while the clear glass in the upper section offers an unobstructed view when the residents are sat on the balcony.  “Everyone is highly satisfied with the results of the renovation work – and that goes for both ourselves in the co-operative’s management team and the tenants themselves. This work is crucial to the economic success of the building project, so it benefits both parties,” says Norbert Hansen, Head of Technical Inventory Management for Kiel East on the success of the renovations, which took over three years to complete.