The EWZ buildingThe EWZ building
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
NatVent
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
The EWZ building was completed in 1994.
The building is situated in the northern part of Zurich in an urban area.
It is a five storey triangular shaped building, with two sides facing busy roads in a congested urban area.
It is designed to protect the occupants from noise and air pollution.
The façades provide a noise barrier and four atria are included (two on the north-side and two on the south-side) to provide maximum daylighting and natural ventilation.
Thanks to its massive construction the building has a high thermal mass
The EWZ building was completed in 1994.
The building is situated in the northern part of Zurich in an urban area.
It is a five storey triangular shaped building, with two sides facing busy roads in a congested urban area.
It is designed to protect the occupants from noise and air pollution.
The façades provide a noise barrier and four atria are included (two on the north-side and two on the south-side) to provide maximum daylighting and natural ventilation.
Thanks to its massive construction the building has a high thermal mass
Project presentation Project presentation (1...)(1...)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
It is a five storey triangular shaped building, with two sides facing busy roads in a congested urban area.
It is a five storey triangular shaped building, with two sides facing busy roads in a congested urban area.
Project presentation Project presentation (2...)(2...)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Mechanically Mechanically ventilated ventilated officesoffices
Mechanically Mechanically ventilated ventilated officesoffices
Naturally ventilated Naturally ventilated officesofficesNaturally ventilated Naturally ventilated officesoffices
Mechanically Mechanically ventilated atriaventilated atriaMechanically Mechanically ventilated atriaventilated atria
Project presentation Project presentation (3|)(3|)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
A two step hybrid ventilation concept was chosen to meet energy and comfort demands: The four atria are mechanically ventilated during the day, but
provide manual window access to the surrounding offices which are naturally ventilated.
At night time the atria and the offices are naturally ventilated.
Decentralised ventilation units are used to reduce ductwork and energy use.
The main target of this project was to design an energy efficient multi-use building, both in construction and in use.
After completion of the building, the aim is to achieve further energy savings during operation together with good indoor environment.
A two step hybrid ventilation concept was chosen to meet energy and comfort demands: The four atria are mechanically ventilated during the day, but
provide manual window access to the surrounding offices which are naturally ventilated.
At night time the atria and the offices are naturally ventilated.
Decentralised ventilation units are used to reduce ductwork and energy use.
The main target of this project was to design an energy efficient multi-use building, both in construction and in use.
After completion of the building, the aim is to achieve further energy savings during operation together with good indoor environment.
The design issue The design issue (1...)(1...)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
The design issue The design issue (2|)(2|)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
The building concept The building concept (1...)(1...) ventilation strategy ventilation strategy during summerduring summer
Off
ices
Off
ices
Atr
ia
… for the Atria: During working hours:
Mechanical ventilation with heat recovery and central cooling.
At night: Natural ventilation by window opening in the atria.
… for the Offices : Natural ventilation by manual
opening the windows facing the atria.
… for the Atria: During working hours:
Mechanical ventilation with heat recovery and central cooling.
At night: Natural ventilation by window opening in the atria.
… for the Offices : Natural ventilation by manual
opening the windows facing the atria.
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
The mechanical ventilation system is equipped with a central heat recovery unit to reduce the energy losses during the heating season.
Moreover, the ventilation is turned off outside office hours
The mechanical ventilation system is equipped with a central heat recovery unit to reduce the energy losses during the heating season.
Moreover, the ventilation is turned off outside office hours
Heat Recovery UnitHeat Recovery UnitHeat Recovery UnitHeat Recovery Unit
Exhaust AirExhaust AirExhaust AirExhaust Air
Supply AirSupply AirSupply AirSupply Air
Fresh AirFresh AirFresh AirFresh Air
The building concept The building concept (2...)(2...) low energy use in winter timelow energy use in winter time
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Ice stack is loaded during the night to cool during the day. The atria are then ventilated, with a projected air exchange rate of 5 h-1 (pre-cooled air at 16 to 17°C). To properly mix the air in the atria ventilators are installed.
In addition night cooling is applied by automatically opening the top windows in the atria.
To reduce solar impact there are motorised shading devices (external screens) on the side walls and atria roofs.
There is no active cooling in the offices !
(Schematic - see next slide…)
Ice stack is loaded during the night to cool during the day. The atria are then ventilated, with a projected air exchange rate of 5 h-1 (pre-cooled air at 16 to 17°C). To properly mix the air in the atria ventilators are installed.
In addition night cooling is applied by automatically opening the top windows in the atria.
To reduce solar impact there are motorised shading devices (external screens) on the side walls and atria roofs.
There is no active cooling in the offices !
(Schematic - see next slide…)
The building concept The building concept (3...)(3...) overall strategy for summer comfortoverall strategy for summer comfort
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
External External screensscreensExternal External screensscreens
NightNightNightNight DayDayDayDay
Ice stack Ice stack loadload
Ice stack Ice stack loadload
Night Night CoolingCoolingNight Night
CoolingCoolingMixing Mixing FansFans
Mixing Mixing FansFans Cooled AirCooled Air
(Outside air is (Outside air is pre-cooled by pre-cooled by the Ice stack the Ice stack load: 16 to load: 16 to
17°C)17°C)
Cooled AirCooled Air
(Outside air is (Outside air is pre-cooled by pre-cooled by the Ice stack the Ice stack load: 16 to load: 16 to
17°C)17°C)
The building concept The building concept (4...)(4...) overall strategy for summer comfortoverall strategy for summer comfort
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
The ventilation concept was chosen to meet comfort demands.
Concept: The atria is mechanically ventilated and provides manual window access to the surrounding offices which are naturally ventilated.
Control: The air change rate in the office is chosen by the users as they wish.
The ventilation concept was chosen to meet comfort demands.
Concept: The atria is mechanically ventilated and provides manual window access to the surrounding offices which are naturally ventilated.
Control: The air change rate in the office is chosen by the users as they wish.
NatVent
Off
ices
Off
ices
Atr
iaA
tria
The building concept The building concept (5|)(5|) indoor air quality during office hoursindoor air quality during office hours
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Monitoring set-upMonitoring set-up Continuous measurements of carbon dioxide (CO2 ) / ventilation rate /
temperature / humidity / indoor air velocity (in the offices)
were made over one week periods during February 1997, July 1997,
in atrium 2 (right side of the south façade of the building) three cellular offices on the first, second fourth floor of the atrium 2 (fully
monitored) atrium 1 (left side of the south façade of the building) three cellular offices on the first, second fourth floor of the atrium 2 (only
temperature)
The following offices were considered as representative: for winter: a cellular office on the second floor surrounding atrium 2 for summer: a cellular office on the first floor surrounding atrium 2
. The monitoring results of these offices are shown in the following charts
Continuous measurements of carbon dioxide (CO2 ) / ventilation rate / temperature / humidity / indoor air velocity (in the offices)
were made over one week periods during February 1997, July 1997,
in atrium 2 (right side of the south façade of the building) three cellular offices on the first, second fourth floor of the atrium 2 (fully
monitored) atrium 1 (left side of the south façade of the building) three cellular offices on the first, second fourth floor of the atrium 2 (only
temperature)
The following offices were considered as representative: for winter: a cellular office on the second floor surrounding atrium 2 for summer: a cellular office on the first floor surrounding atrium 2
. The monitoring results of these offices are shown in the following charts
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
-5
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
07-09.02.1997
Ind
oo
r a
nd
ou
tsid
e t
em
pa
ir c
ha
ng
e r
ate
0
200
400
600
800
1000
1200
Ca
rbo
n d
iox
ide
Indoor Temp.- office [°C] Air Change - office [1/h] Outside Temp. [°C]
Atrium Temp. [°C] Carbon Dioxide [ppm]
Winter monitoring Winter monitoring (1...)(1...) typical winter day - monitoring resultstypical winter day - monitoring results
Slight overheating in offices due to problems with automatic control of the shading devices
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
-5
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
07-09.02.1997
Ind
oo
r a
nd
ou
tsid
e t
em
pa
ir c
ha
ng
e r
ate
0
200
400
600
800
1000
1200
Ca
rbo
n d
iox
ide
Indoor Temp.- office [°C] Air Change - office [1/h] Outside Temp. [°C]
Atrium Temp. [°C] Carbon Dioxide [ppm]
Winter monitoring Winter monitoring (2...)(2...) typical winter day - monitoring resultstypical winter day - monitoring results
Good IAQ: low CO2 concentration during office hours (far below 1200 ppm)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
-5
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
07-09.02.1997
Ind
oo
r a
nd
ou
tsid
e t
em
pa
ir c
ha
ng
e r
ate
0
200
400
600
800
1000
1200
Ca
rbo
n d
iox
ide
Indoor Temp.- office [°C] Air Change - office [1/h] Outside Temp. [°C]
Atrium Temp. [°C] Carbon Dioxide [ppm]
Winter monitoring Winter monitoring (3|)(3|) typical winter day - monitoring resultstypical winter day - monitoring results
Low air change rate is sufficient: good air quality
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Summer monitoring Summer monitoring (1...)(1...) typical summer day - monitoring resultstypical summer day - monitoring results
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
23-25.07.1997
Ind
oo
r a
nd
ou
tsid
e t
em
p a
ir c
ha
ng
e r
ate
Indoor Temp. [°C] Outside Temp. [°C] Atrium Temp. [°C]
Good thermal comfort in office: Tint = 23°C while Text goes to 33°C:
Remark: This results is partially the result of active cooling in the atrium
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
-5
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
23-25.07.1997
Ind
oo
r a
nd
ou
tsid
e t
em
p a
ir c
ha
ng
e r
ate
0
200
400
600
800
1000
1200
Ca
rbo
n d
iox
ide
Indoor Temp.- office [°C] Air Change - office [1/h] Outside Temp. [°C]
Atrium Temp. [°C] Carbon Dioxide [ppm]
Summer monitoring Summer monitoring (2...)(2...) typical summer day - monitoring resultstypical summer day - monitoring results
Good IAQ: low CO2 concentration during office hours (far below 1200 ppm)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
-5
0
5
10
15
20
25
30
35
40
12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00
23-25.07.1997
Ind
oo
r a
nd
ou
tsid
e t
em
p a
ir c
ha
ng
e r
ate
0
200
400
600
800
1000
1200
Ca
rbo
n d
iox
ide
Indoor Temp.- office [°C] Air Change - office [1/h] Outside Temp. [°C]
Atrium Temp. [°C] Carbon Dioxide [ppm]
Summer monitoring Summer monitoring (3|)(3|) typical summer day - monitoring resultstypical summer day - monitoring results
Air change rates are sufficient good IAQ
However no ventilation during the night to cool the office: window is closed
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Night Cooling of the atria: Thanks to the architecture the stack effect in the atria can be considered to
provide a sufficiently strong force for natural ventilation; On the other hand a re-evaluation of the dimensions of the openings could
increase night ventilation resulting in a better natural night cooling.
Night Cooling of the offices - Barriers Night cooling in the atria only takes place if atria windows are open. The atria
windows are in this case automatically open if outside temperature is three degrees lower than the air temperature in the atria (this a typical strategy for mechanical night cooling). For natural night cooling the atria windows should automatically open if outside temperature is lower than the air temperature in the atria
Night cooling in the offices only takes place if the office windows have been left open after the end of the working days. Closed office windows and doors form a large obstruction for the natural night cooling. The best night cooling efficiency is achieved by cross ventilation through window and door.
Night Cooling of the atria: Thanks to the architecture the stack effect in the atria can be considered to
provide a sufficiently strong force for natural ventilation; On the other hand a re-evaluation of the dimensions of the openings could
increase night ventilation resulting in a better natural night cooling.
Night Cooling of the offices - Barriers Night cooling in the atria only takes place if atria windows are open. The atria
windows are in this case automatically open if outside temperature is three degrees lower than the air temperature in the atria (this a typical strategy for mechanical night cooling). For natural night cooling the atria windows should automatically open if outside temperature is lower than the air temperature in the atria
Night cooling in the offices only takes place if the office windows have been left open after the end of the working days. Closed office windows and doors form a large obstruction for the natural night cooling. The best night cooling efficiency is achieved by cross ventilation through window and door.
Major findings Major findings (1...)(1...)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Shading devices: In the winter, the shading devices , which close automatically, did
not close at the right time. Therefore offices are sometimes lightly overheated and illuminated with too much direct sun light.
The automatically shading devices in summer achieved the expected aims. The thermal comfort in summertime is optimal (remark: in summer active cooling is used in the atria).
The Indoor Air Quality is always acceptable
Occupant Reactions: The occupants are very satisfied with the building.One of the
main reasons is that they appreciate being able to open the windows.
Shading devices: In the winter, the shading devices , which close automatically, did
not close at the right time. Therefore offices are sometimes lightly overheated and illuminated with too much direct sun light.
The automatically shading devices in summer achieved the expected aims. The thermal comfort in summertime is optimal (remark: in summer active cooling is used in the atria).
The Indoor Air Quality is always acceptable
Occupant Reactions: The occupants are very satisfied with the building.One of the
main reasons is that they appreciate being able to open the windows.
Major findings Major findings (2...)(2...)
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
In General: The EWZ building is a good example of a pragmatic approach.
The hybrid concept combines active cooling and passive elements like night cooling and shading devices. The concept provides high quality indoor comfort at any external condition.
Energy consumption: The EWZ building can be considered as a building with a rather
low energy consumption. A further reduction of the energy consumption can be achieved by an optimisation of the heating level in winter and the electricity consumption for the cooling and for the mechanical ventilation.
In General: The EWZ building is a good example of a pragmatic approach.
The hybrid concept combines active cooling and passive elements like night cooling and shading devices. The concept provides high quality indoor comfort at any external condition.
Energy consumption: The EWZ building can be considered as a building with a rather
low energy consumption. A further reduction of the energy consumption can be achieved by an optimisation of the heating level in winter and the electricity consumption for the cooling and for the mechanical ventilation.
Major findings Major findings (3|)(3|)
More information...More information...
NatVent
Presentation Presentation of the buildingof the building
The design The design issueissue
The building The building conceptconcept
The winter The winter monitoringmonitoring
The summer The summer monitoringmonitoring
Major Major findingsfindings
The EWZ The EWZ buildingbuilding
More More information...information...
Back to Back to “Select a “Select a building”building”
Find more information on the PROBE building in the following documents:
\Reports \Monitoring Reports \Summary Reports\ch2summ.pdf global presentation of the buildings (4p./building) contents: building description - ventilation strategy and technology -
winter and summer monitoring results - conclusions
\Reports \Monitoring Reports \Detailed Reports\ch2det.pdf detailed reports of all 19 monitoring campaigns (20p./campaign) contents: monitoring set up - analysis of results - conclusions
Find more information on the PROBE building in the following documents:
\Reports \Monitoring Reports \Summary Reports\ch2summ.pdf global presentation of the buildings (4p./building) contents: building description - ventilation strategy and technology -
winter and summer monitoring results - conclusions
\Reports \Monitoring Reports \Detailed Reports\ch2det.pdf detailed reports of all 19 monitoring campaigns (20p./campaign) contents: monitoring set up - analysis of results - conclusions
You can read and print pdf-files with the Acrobat® Reader ®3.0. Program. This program is free.
Download it from the Acrobat web site: www.adobe.com OR run the installation file ar32e301(1).exe in the directory \Installation
You can read and print pdf-files with the Acrobat® Reader ®3.0. Program. This program is free.
Download it from the Acrobat web site: www.adobe.com OR run the installation file ar32e301(1).exe in the directory \Installation