Re-use in Kungsholmen

Ola Mortensen,
Project Manager, Castellum

Robert Carlsson,
Sustainability Manager, Castellum

The island and district of Kungsholmen in central Stockholm has undergone a major transformation over the last few decades. Old industry land has been remediated, and provided space for attractive residences and offices. Centrally located and with excellent communication for rail traffic, cars, and buses, and also well-constructed infrastructure for cyclists and pedestrians. The Hornsberg neighbourhood has become one of Stockholm’s most expansive business districts. In recent years, many purpose-driven companies have established themselves in the neighbourhood, which utterly breathes the future.

­Castellum has operations in Kungsholmen, and when the company decided to renovate the Hornsberg 10 property, the goal was to do so in as climate-smart a manner as possible. “Construction companies are so used to tearing out everything instead of saving whatever is still in good condition,” says Ola Mortensen, project manager at Castellum. During the reconstruction, -Castellum chose to investigate what materials could be saved and re-used so as to build more sustainably.

New construction material should be re-usable

Re-use concerns extending the lifetime of a product, and the gains from this are numerous. Both new manufacture and consumption of new materials and products are avoided to a great extent, which is good for the climate, the environment, and the economy. At the Hornsberg property, it was possible to re-use everything from doors and windows to the porcelain in toilets and sinks. Things that normally would have been discarded have been saved. This reduced demolition costs, and also kept the investment requirements in the project down.

The Hornsberg property was converted from cell offices to an open plan solution. An additional sustainability aspect in the project is that -Castellum installed sprinklers more closely together than the traditional approach, in order to avoid reconstruction and thereby reducing the climate impact when the premises are customised according to tenants’ design needs.

­Castellum is also part of a research project with IVL Svenska Miljöinstitutet in which construction data is analysed to determine the climate impact of the project. Guidance on how to reduce climate impact during renovation and reconstruction will be developed.

Windows from Kungsholmen get a new life in Estonia

­Castellum partnered with the recycling broker Kompanjonen on the project. “Over the course of the project, we also accumulated crucial know-how regarding re-use for future projects,” says Robert Carlsson, sustainability manager -at Castellum. A total of 170 doors, 300 windows and 200 glass partitions were dismantled and saved for re-use. The windows were given a new life at a construction project in Estonia. The total climate savings for the aforementioned projects was 34 tonnes of carbon dioxide, which corresponds to driving a car 136,000 kilometres – almost 3.5 times around the world at the equator.

At the Hornsberg 10 property, Castellum is developing Martin & Servera’s new head office, which will house 400 employees and be ready for occupancy in August of 2023. Since the very start of the total renovation, Castellum has focused on re-use, where the material being removed is either re-used in the project or is given life in other buildings.

Castellum and re-use

  • As of 2022: Re-use in all projects
  • 2030: Re-use and renewable materials must be a significant element in all projects.
  • Castellum has signed framework agreements with suppliers that will proved assistance in the area of re-use.