Westraven is a sustainable office building located in Utrecht, Netherlands, designed by Cepezed Architects, with a total area of 53,000 m2, including 23,000 m2 of new construction and 27,000 m2 of renovation, completed in 2007. The building employs innovative techniques such as concrete core activation for temperature regulation, biodynamic lighting that adapts to human circadian rhythms, and a second-skin façade to enhance energy efficiency while allowing natural ventilation. The design includes distinct climate zones to create an optimal working environment with minimal energy use.

1. WESTRAVEN
A.B.C.
Sem- 8th
Preyan Mehta

2. WESTRAVEN
Location: Griffioenlaan 2, Utrecht, Netherlands
Client: Ministry of Housing And Construction
Gfa: Total 53,000 m2; New construction 23,000 m2;
Renovation 27,000 m2; Grounds And Entrance 3,000 m2
Realization: 2007
Photography: Jannes Linders

3. WESTRAVEN
Integral building
The new office is an example of integral building. The old
Office tower originates from 1973 and used to be a so-called
“sick building” dealing with problems such as a bad indoor
climate, asbestos and a leaking house front. The existing
tower is surrounded by new construction of low building
wings.
The visionary architectural concept of the architect’s firm
Cepezed required an innovative approach to installation
Which Grontmij realised.

4. WESTRAVEN
Sustainable techniques
In the building many sustainable
technique have been used such as
‘concrete core activation’. This is a way
of cooling and warming the building
that uses the building mass and
which is integrated in the floor
construction. This technique is combined
With energy storage in the ground and
the utilization of warmth pumps.
By storing warmth or cold in the ground
and using this in another season the
indoor climate is kept to the desired
Additionally there are four climate zones
in this building: an office climate,
conservatory climate, entrance climate
and a courtyard garden climate
(sheltered from the wind).
These climate zones form the basis of the integral design.
temperature with minimum energy use.

5. WESTRAVEN
A passive intelligent building
The goal of this building was to build an intelligent building
that can adapt to different uses and different external
influences. Examples of this built-in intelligence are:
Cooling and warming via ‘concrete core activation’
The building front which keeps most of the wind and sun
out without completely shutting them out.
Conservatories which dampen the climate influences from
outside and have a useful function.

6. WESTRAVEN
Biodynamic lighting
In this project it is the first time that biodynamic lighting is used
at such a large scale. The system is derived from the Carpe
diem system of Philips, but is not entirely the same as it uses
different fittings. The intensity of the light and the light colour
is adapted to a human’s biological clock. The light and the
colour of the light changes gradually during the day.

7. WESTRAVEN
A word by Architect
Much attention has been devoted to realizing perfect
equilibrium between low energy consumption and an optimum
working climate. For this purpose, an ingenious climate
concept has been developed which makes use of thermally
active floors. Various types of space have been climatized
differently, the heat of air flows is recovered at several points
and the artificial lighting adapts itself automatically to the
colour and intensity of the incidence of daylight.
Furthermore, a revolutionary feature is the innovative
second-skin façade of open-weave, teflon-coated glass fibre
that offers all-round protection against the wind and makes it
possible to work with open windows, even on the top floors.
As a result, the staff enjoy great freedom is regulating their
own interior climate, which is quite a luxury for high-rise
construction.

8. WESTRAVEN
Preyan Mehta
21(B.Arch(C.T.)/10)
Location: Griffioenlaan 2, Utrecht, Netherlands
Client: Ministry of Housing And Construction
Gfa: Total 53,000 m2; New construction 23,000 m2;
Renovation 27,000 m2; Grounds And Entrance 3,000 m2
Realization: 2007
Photography: Jannes Linders
Architects: CEPEZED Architects.
SEM- 8th