Industrialised, Integrated, Intelligent sustainable Construction - I3con

SUSTAINABLE CONSTRUCTION HANDBOOK 2
To see the influence of individual components on the total performance of the façade, a reference
situation has been defined from which changes in the settings are assessed. Using the reference
situation as a starting point, the parameters have been refined until favourable conditions were
achieved. The input is listed in Table 1:
Table 1. Simulation model input of south facade
Efficiency heat exchanger [%] 70%
Bypass of heat exchanger if Night vent. on or windows open
Temperature windows open [°C] 24°C
Temperature windows close [°C] 23°C
Influence openable windows [added to ventilation rate] 0.5 extra rate
G-value change from 0.65 (no shading) to 0.15 [°C] 23°C
Dimensions façade element: Width of the element 1200 mm
Floor height 3000 mm
Parapet height 750 mm
Glass height 2000 mm
U-value glass/frame/parapet [W/m 2 K] 1.0/2.0/0.25 W/m 2 K
Window frame percentage of the glass area 25%
Dimensions PCM [m] / number of layers 0.005 thick *0.45 m high / 90
Minimum ventilation flow rate day [m 3 /s] 0.0108 m 3 /s
Maximum ventilation flow rate day [m 3 /s] 0.0216 m 3 /s
Added ventilation during day 0.0054 m 3 /s per °C above 22°C
Min. temp. difference indoor-outdoor night vent. [°C] 2°C
Night ventilation only if operative indoor temperature > 22°C
Night heating only if indoor temperature < 20°C
Conditions night heating: air temp ex. PCM below? [°C] 18°C
Internal heat load [W/m 2 ] 30 W/m 2
Internal heat load only on workdays from 8-18 hours
Indoor space
The nature of the climate adaptive skin allows the indoor space to be free of a lowered ceiling,
meaning that the thermal mass of both the floor and the (concrete) ceiling can be used to influence the
indoor temperature in the simulations. It is not designed to have a specific width, but designed to be
able to condition the adjacent office space, which is a standard 5.4 m deep. As such, it can be
multiplied by any number in horizontal direction; the width of a CAS element is therefore chosen to
be 1.2 meter, which is more or less a standard grid size in The Netherlands.
For the indoor heat production an average of 30 W/m 2 for people, equipment and lighting is taken.
The transparent part of the façade equals roughly 2 m 2 through which solar irradiation heats up the
indoor climate. The U-value of the window frames is generally much higher than that of the window
itself, and is therefore also included into the simulation model.
Ventilation unit
The unique element in the Climate Adaptive Skin, and one of its vital parts, is the ventilation unit.
This unit contains a number of elements and is responsible for the provision and conditioning of fresh
ventilation air.
Heat exchanger
Stale air from the indoor environment is used to preheat incoming ventilation air using a cross-flow
heat exchanger to reduce the electricity demand for heating. In earlier simulations without either
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