New micro-hotel opens in Copenhagen boathouse
Meet Kaj: Copenhagen's newest sustainable micro-hotel, designed as a private boathouse using recycled materials

The Copenhagen architecture scene is full of must-sees – from modernist masterpieces to contemporary marvels, such as OMA's BLOX. Yet there are also some smaller gems that bring a sense of architectural experimentation to the everyday for the discerning visitor – such is Kaj, the town's latest sustainable micro-hotel, which has been designed as a boutique, one-room boathouse you can rent.
It all started when owners and partners in work and life Barbara von Haffner and Toke Larsen spotted a gap in the market. With the help of architect Karl Smith Meyer, they decided to put a plan into action.
‘We have often been contacted by people who wanted to rent our houseboat or asked what it is like to live on it,' they say. ‘The idea for KAJ Hotel arose in the wake of these questions, which were almost impossible to answer unequivocally, as the experience varies depending on wind and weather conditions, as well as what time of day – or year – one stays there. One has to try it out for one self – and every moment has its own charm.'
Now, set on Copenhagen harbour and built literally on the water, Kaj is created primarily in recycled wood. Its structure was partially prefabricated (on the deck of the couple's houseboat) and craned directly into the site. Von Haffner also leads Undercover Copenhagen, a company specialising in recycled and sustainable fabrics, while the couple's own home was created using environmentally friendly ways, so looking at this project from an eco-friendly angle came naturally to the pair.
As a result, the historic window frames, for example, used to belong to a former Danish Defense Command building; the foundations make use of old railroad poles; and the stairs and gangway are recycled from an actual ship.
Inside, modern minimalism meets a Scandinavian aesthetic with a distinct domestic feel. A master suite and a further bedrooms on a mezzanine can sleep up to four people and a baby. Even though spanning a mere 16 sq m, the boathouse feels spacious and comfortable thanks to a neutral, calming colour and material palette, large windows that allow the eye to wonder, and a terrace. This is as close to a houseboat as you can get, without actually being on one – it even comes with its own boat.
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Ellie Stathaki is the Architecture & Environment Director at Wallpaper*. She trained as an architect at the Aristotle University of Thessaloniki in Greece and studied architectural history at the Bartlett in London. Now an established journalist, she has been a member of the Wallpaper* team since 2006, visiting buildings across the globe and interviewing leading architects such as Tadao Ando and Rem Koolhaas. Ellie has also taken part in judging panels, moderated events, curated shows and contributed in books, such as The Contemporary House (Thames & Hudson, 2018), Glenn Sestig Architecture Diary (2020) and House London (2022).
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