top of page



K1 – Karlbergs Strand






Stockholm, Sweden


In the autumn of 2015, Fastighetsvärlden was able to reveal that JM planned to move its head office from Frösunda to Karlberg.
K1 Karlbergs strand is an office property of just over 20,000 sqm. The property, which will be environmentally certified according to LEED Platinum, will house both JM's new head office and space for external tenants.
The collaboration with Solna Stad and Wingårdhs has contributed to the opportunity to develop sustainable, modern office premises with lake views in two directions and with recreation areas and city pulse around the corner, just a stone's throw from the subway.

Proper Atrium modelling

A main reason of Inform Design’s involvement was to assist JM with properly modelling the Atrium using a Dynamic Thermal Modelling (DTM) software tool that can properly account for the temperature stratification in the space, as well as the impact of bi-directional flows on the temperature stratification. The aim was to suggest a skylight with maximum daylight benefits while avoiding overheating.
As an one-node model (not accounting for the temperature stratification in the space - well-mixed space) would provide a temperature that corresponds to the vertical and horizontal centre of the Atrium, we were assigned to provide a more accurate assessment using an in-house DTM software tool that can capture such phenomena.


Controls for accurate predictions

Estimating the solar radiation falling on the glazing based on sensors can be a challenge, as the external façade elements will shade different glazing area each hour. As an example, the three measuring points (red dots) will provide rather different output depending on the hour, leading to either overusing the shading or underusing it when it is actually required. We use Dynamic Thermal Modelling Tools to predict the incident and transmitted solar radiation for each hour of the year, taking into account the building’s geometry.
Often shading control systems use a simplified method to estimate the transmitted solar radiation. This method includes recording the incident solar radiation on a façade and multiplying the number with the g-value. The problem with this estimation is that the glass specularity is not considered and the predicted number is often too conservative. This means that the shading will be drawn more often than necessary and predicted by the simulations during the design stage. Our approach is to predict the transmitted solar radiation based on the results from Dynamic Thermal Modelling simulation, that takes into account the sun’s position and the glazing specular properties. This method results in better agreement between predicted and real life performance.


Perimeter facades

Our role was to advise JM on TGU build-ups, (internally placed) shading fabrics and internal venetian blinds that can meet the set requirements and provide a good real life performance. To do so, we needed to take “one step back” and re-examine the effectiveness of different (glazing & shading) configurations with regard to certain parameters, as described below.

bottom of page