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Office building CAW region Bruges, BE Studiebureau Boydens


CAW North-West Flanders building is an energy efficient 7-storey office building with an advanced and integrated energy concept. The GEOTABS building combines the renewable share of geothermal energy (GEO) with a heat pump and a delivery system in the premises by pipes incorporated into the concrete slabs (Thermal Active Building System) or concrete core activation (CCA).
This concept originated in Switzerland around 1995 and further optimized between 2009-2012 by a consortium of public sector companies including Boydens Engineering (who provided technical MEP case study data for the application of this project) together with eight European universities in which KULEUVEN the lead.
Important is the storage of energy in the building mass and in the ground. This allows the building to adapt its electrical demand profile with flexibility to the needs of the distribution network acting as a smart building. Alternatively,
the underground storage system bridges the seasons, heat is stored in the summer months and used in winter to heat the building economically.
The building envelope was optimized by the designers for the total energy demand, over all seasons, and taking into account the actual operation of the building.  The conventional E-level approach (E-level 57, K-level 33) was not possible. The optimization study was further refined by Masters students at Ghent University, which attracted the Marcel Herman's award from the Belgian professional association ATIC.
The building is equipped with a BTES (Borehole thermal energy storage) system, 40 drilled boreholes, each 130m deep, extracting heat from the ground through vertical ground heat exchangers. The BTES is accompanied by a heat pump for lowering the soil/ground temperature.
The heat produced is delivered to the building via concrete core activation without the need of additional fossil fuels. The cooling of the building occurs in a passive manner using the cooled bottom soil/ground. In addition, the east, west and south façade of the building is equipped with outdoor solar shading.   In order to create a healthy indoor climate, a demand-controlled ventilation system with heat recovery is applied.  The lighting in the offices is equipped with daylight control, in order to maximize natural daylight.
Office building CAW region Bruges

general data

total cost price: € 6.919.238,53 VAT excluded

total area: 4.382 m²

Study start date:: August 2013

completion date: April 2017

nature of work: Construction

cost techniques: € 1.661.102,54 VAT excluded


K Level / Energy class : 33
E Level: 57
Certification: -


CAW Noord-West-Vlaanderen vzw


Debruyne Gino en architecten