Trianglen, Østerbrogade

This property, with its distinctive towers, is located on the corner of Østerbrogade/Nordre Frihavnsgade, at Trianglen in Copenhagen. The 5,111-sq.m property houses a total of 30 residential and commercial leases. This classical property was built in 1888 and has been managed by DEAS since 2003.



In 2013, the owner, PKA faced the challenge of renovating the property’s roof.

Since there is high demand in Copenhagen for modern flats at central locations, with a historical profile, the pension fund took the opportunity to convert the property's 706-sq.m. fifth-floor attic into a new floor of flats.


First of all, the customer needed an assessment of whether it was even possible to turn the property’s attic into flats. This concerned whether the municipality would grant a building permit, since local plans might impose maximum heights that made it impossible to elevate the roof structure. There was also the question of the technical feasibility of extending the main staircase, as well as the necessary water, heating and drainage installations.

Moreover, new technical challenges arise when new homes are constructed at the top of an existing building – in particular an older property located at a busy Copenhagen junction – rather than on a vacant plot. The project’s complexity made high demands of execution and the expertise to resolve the unforeseen challenges that inevitably arise along the way.


Client consulting Project development and construction management Letting

DEAS secured a building permit from the City of Copenhagen and undertook the required preliminary work and the engineering research needed to make a decision on the feasibility of the project. On this basis, DEAS’ engineering advisers concluded that the building could bear the additional weight and, equally important, that there was a basis for the new floor to have a good layout.

One of the property’s distinctive towers – before and after it was integrated into the new rooftop homes.

It was decided to establish six flats in total, and DEAS submitted a layout proposal whereby five of the flats included a rooftop terrace. As a substitute for the former attic’s storage space, residents gained a new, 100-sq.m. courtyard building for refuse management and bicycle storage, as well as a communal rooftop terrace. The existing courtyard basement, in need of renovation, was converted into storage rooms.

As client consultant, DEAS took care to choose solutions for the new rental homes that made sense for both tenants and the customer. Materials were chosen that were in harmony with the property’s age and history, so that even small details such as skirting boards were matched to those in the existing flats. The new homes thus retain the look that makes it so attractive to live in a historical property like this one.

DEAS handled this assignment from project development to construction management and client consulting, and the marketing and letting of the six new penthouse flats.


The project commenced on 1 January 2013, and on 1 September 2014, the new flats were ready to receive their new tenants. The homes were rented out after the first viewing in June, when only the bare walls were in place, assuring the customer that all the flats were rented out before completion.

The new penthouse flats vary in size from 83 sq.m. to 152 sq.m., with 2-4 rooms.

The rental income from the new flats will pay for the renovation of the roof over a number of years, making the project a financially sound investment for the customer. Finally, PKA has gained a real increase in the property’s value.

The customer was thus assured of a holistic and well-considered solution from start to finish.

Turnkey contractor and architect: Hald & Halberg / E-KL Architects.


Per Thomassen

Senior Director
Technical Building Consultancy
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