the velux building natvent presentation of the building presentation of the building the design...

The Velux BuildingThe Velux Building

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 VELUX The VELUX buildingbuilding

More More information...information...

Back to Back to “Select a “Select a building”building”

NatVent










Project presentation Project presentation (1...)(1...)

The Velux building is situated in central Switzerland in the tableland.

This area is characterised by a moderate and sometimes windy climate.

The building was renovated in 1992: the former flat roof was topped by two additional floors with tilted outside walls resulting in the new roof.

The building is used as an administration building of a factory for window fittings.

The building has many cellular offices, an open plan office and a big show room. The rooms have a lot of internal mass: exposed ceilings and tiled floors (the internal walls and external walls are light-weight constructions).

The Velux building is situated in central Switzerland in the tableland.

This area is characterised by a moderate and sometimes windy climate.

The building was renovated in 1992: the former flat roof was topped by two additional floors with tilted outside walls resulting in the new roof.

The building is used as an administration building of a factory for window fittings.

The building has many cellular offices, an open plan office and a big show room. The rooms have a lot of internal mass: exposed ceilings and tiled floors (the internal walls and external walls are light-weight constructions).

NatVent











A production facilities for windows fittings is attached to the back of the building.

The building is located in a quiet industrial zone next to a low frequented road at the edge of a river. Noise and pollution are not a problem.

A production facilities for windows fittings is attached to the back of the building.

The building is located in a quiet industrial zone next to a low frequented road at the edge of a river. Noise and pollution are not a problem.

Part under investigation

NatVent











Part under investigationFactory

Cellular Cellular officesoffices

Cellular Cellular officesoffices

Open plan Open plan officeoffice

Open plan Open plan officeoffice

NatVent











1st floor

The basement and the The basement and the two lower floors consist of two lower floors consist of

cellular officescellular offices..

The basement and the The basement and the two lower floors consist of two lower floors consist of

cellular officescellular offices..

NatVent










Project presentation Project presentation (5|)(5|)

3rd floor

The two top floors are The two top floors are designed as an designed as an open open plan officeplan office (2 (2dndn floor) floor) and a and a show roomshow room (3 (3rdrd

floor).floor).

The two top floors are The two top floors are designed as an designed as an open open plan officeplan office (2 (2dndn floor) floor) and a and a show roomshow room (3 (3rdrd

floor).floor).

NatVent










The design issue The design issue (1...)(1...)

Windows furnishedwith electronic actuators

As the building is used for the administration of a window fitting factory, window fixtures and fittings are seen as very important features by the occupants.

Windows furnished with electronic actuators represent one of the new products of the company.

The windows are automatically controlled with a manual override . This improves the user-acceptance.

As the building is used for the administration of a window fitting factory, window fixtures and fittings are seen as very important features by the occupants.

Windows furnished with electronic actuators represent one of the new products of the company.

The windows are automatically controlled with a manual override . This improves the user-acceptance.

NatVent










The design issue The design issue (2|)(2|)

To achieve the goals three control strategies were used: Automatically timer controlled system (e.g. for night ventilation and

cross ventilation during the work breaks), Automatically opened windows depending on weather conditions

(e.g. wind velocity, rain). Manual operated system (The windows can also be manually

controlled during working hours),

To achieve the goals three control strategies were used: Automatically timer controlled system (e.g. for night ventilation and

cross ventilation during the work breaks), Automatically opened windows depending on weather conditions

(e.g. wind velocity, rain). Manual operated system (The windows can also be manually

controlled during working hours),

The aim is for the occupants to get natural ventilation via the windows with electronic actuators.

Thanks to the open architecture of the staircase of the building the stack effect is considered to provide a sufficiently strong force for ventilation.

The aim is for the occupants to get natural ventilation via the windows with electronic actuators.

Thanks to the open architecture of the staircase of the building the stack effect is considered to provide a sufficiently strong force for ventilation.

NatVent










The building concept The building concept (1...)(1...) Indoor Air Quality during office hoursIndoor Air Quality during office hours

Strategy for IAQ:

During breaks (early in the morning and at noon) the windows are automatically (time controller) opened for 5 minutes to ventilate the building.

During the heating season, the building is only ventilated during some periods to avoid too high ventilation losses

Strategy for IAQ:

During breaks (early in the morning and at noon) the windows are automatically (time controller) opened for 5 minutes to ventilate the building.

During the heating season, the building is only ventilated during some periods to avoid too high ventilation losses

NatVent










The building concept The building concept (2...)(2...) global strategy for summer comfortglobal strategy for summer comfort

The risk of overheating is reduced by:

Shading devices: external screens are installed on the all façades. The screens are controlled manually.

The building and the thermal mass (exposed ceilings) of the building is cooled down by intensive ventilation based on the stack effect. The windows are automatically opened:

during working hours in the afternoon if the outside temperature is higher than the inside temperature

at night (time control)

Moreover, the automatic control of the windows take weather conditions into account (see next slide... ).

The risk of overheating is reduced by:

Shading devices: external screens are installed on the all façades. The screens are controlled manually.

The building and the thermal mass (exposed ceilings) of the building is cooled down by intensive ventilation based on the stack effect. The windows are automatically opened:

during working hours in the afternoon if the outside temperature is higher than the inside temperature

at night (time control)

Moreover, the automatic control of the windows take weather conditions into account (see next slide... ).

NatVent










The building concept The building concept (3...)(3...) automatic control & outside conditionsautomatic control & outside conditions

Ventilation control is a function of external conditions (see schematic).

The outside conditions are measured by rain and wind sensors.

nice weather nice weather and wind

rain rain and wind

south-west south-east north-east south-west south-east north-east

3rd floor

2nd floor

1st floor

Ground floor

Basement

3rd floor

2nd floor

1st floor

Ground floor

Basement

closed

always closed (security)

open

NatVent










The building concept The building concept (4...)(4...) overviewoverview

SummertimeSummertimeSummertimeSummertime WintertimeWintertimeWintertimeWintertime

during office during office hourshours


outside outside office hoursoffice hours


time-controlled short time ventilation during breaks - to improve IAQ

if Text< Tint: intensive ventilation (weather controlled) - to improve summer comfort


if Text< Tint: intensive ventilation (weather controlled) - to improve summer comfort

intensive ventilation (weather controlled) - to improve summer comfort

intensive ventilation (weather controlled) - to improve summer comfort







no ventilationno ventilation

NatVent










The building concept The building concept (5|)(5|) user acceptance through independence user acceptance through independence

during working hoursduring working hours

All the automatically controlled windows can also be controlled manually (see control device). This permits the building users to operate the desired windows during the working hours in accordance with their required comfort.

This increases the user acceptance of the system.

NatVent










Slide with monitoring set-upSlide with monitoring set-up Continuous measurements of

Carbon Dioxide (CO2 ), Ventilation Rate, Temperature Humidity, Indoor air velocity

were made over one week periods during February 1997, August 1997,

in the meeting room in the basement one cellular office on the ground floor two cellular offices on the first floor (south-west and north-east façade) one open plan on the second floor the show room on the third floor

The cellular office on the first floor on the south-west building side was selected as being representative. The monitoring results of this office is shown in the following chart.

Continuous measurements of Carbon Dioxide (CO2 ), Ventilation Rate, Temperature Humidity, Indoor air velocity

were made over one week periods during February 1997, August 1997,

in the meeting room in the basement one cellular office on the ground floor two cellular offices on the first floor (south-west and north-east façade) one open plan on the second floor the show room on the third floor

The cellular office on the first floor on the south-west building side was selected as being representative. The monitoring results of this office is shown in the following chart.

NatVent










-10

-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

26-28.02.1997

Ind

oo

r a

nd

ou

tsid

e t

em

p. -

air

ch

an

ge

ra

te

Indoor Temperature [°C] Air Change [1/h] Outside Temperature [°C]

Winter monitoring Winter monitoring (1...)(1...) typical winter day - monitoring resultstypical winter day - monitoring results

Indoor temperature sometimes too high due to problem with control of heating system

Occupants open the windows because of too high temperatures relatively high ventilation losses

No ventilation at night = No ventilation losses

NatVent










Winter monitoring Winter monitoring (2...)(2...) typical winter day - monitoring resultstypical winter day - monitoring results

-10

-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

26-28.02.1997

Ind

oo

r an

d o

uts

ide

tem

p.

air

chan

ge

rate

,

0

200

400

600

800

1000

1200

CO

2 co

nce

ntr

.

Indoor Temperature [°C] Air Change [1/h] Outside Temperature [°C] Carbon Dioxide [ppm]

CO2 rises during the office hours never above 1200 ppm (max. conc. :guideline)

Good Indoor Air Quality

Windows are during some minutes autom. opened in the morning

NatVent










Winter monitoring Winter monitoring (3|)(3|) typical winter day - monitoring resultstypical winter day - monitoring results

Due to a problem with the control of the heating system, indoor temperatures were too high. For this reason windows were manually opened to cool the building. This leads to high ventilation losses. It is clear that a better heating control will result in a considerable reduction of the heating consumption in wintertime.

At night all windows are well closed to avoid ventilation losses.

The IAQ in the offices is always acceptable (<1200ppm).

Due to a problem with the control of the heating system, indoor temperatures were too high. For this reason windows were manually opened to cool the building. This leads to high ventilation losses. It is clear that a better heating control will result in a considerable reduction of the heating consumption in wintertime.

At night all windows are well closed to avoid ventilation losses.

The IAQ in the offices is always acceptable (<1200ppm).

NatVent










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

25-27.08.1997

Ind

oo

r a

nd

ou

tsid

e t

em

p.

air

ch

an

ge

ra

te,

IndoorTemperature [°C] Air Change [1/h] Outside temperature [°C]

Very warm day (34°C)

Acceptable peak indoor temperature (28°C)

Intensive night ventilation ( >10 ACH )

Indoor temperature drops due to night ventilation

NatVent










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

25-27.08.1997

Ind

oo

r a

nd

ou

tsid

e t

em

p.

air

ch

an

ge

ra

te,

IndoorTemperature [°C] Air Change [1/h] Outside temperature [°C]

= Windows are automatically opened at 8,13 and 18h to improve the IAQ. The other ventilation peaks are due to manually opened windows.

The influence on the IAQ is given on next slide...

Summer monitoring Summer monitoring (2...)(2...) typical summer day - monitoring resultstypical summer day - monitoring results

Intensive night ventilation (>10 ACH)

NatVent










Summer monitoring Summer monitoring (3|)(3|) 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

25-27.08.1997

Ind

oo

r a

nd

ou

tsid

e t

em

p.

air

ch

an

ge

ra

te,

0

200

400

600

800

1000

1200

Ca

rbo

n d

iox

ide

IndoorTemperature [°C] Air Change [1/h]

Outside temperature [°C] Carbon dioxide [ppm]

There is a clear relation between IAQ during the office hours and the air change rate: High ventilation rate low CO2 concentration

The IAQ is always below the limit of 1200 ppm

NatVent










Major findings Major findings (1...)(1...) summer comfortsummer comfort

Summer comfort: Thanks to the night ventilation and the shading devices, big overheating

problems were avoided.

Shading devices: The efficacy of the external screens could be increased by an automatic

control instead of manual control.

Night Cooling: For security reasons, windows on the ground floor are not opened at

night no night cooling. Therefore the offices on the ground floor have an appreciable overheating problem in summer.

User behaviour: Closed doors during the night obstruct often the night cooling in summertime. Clear user instructions could help.

A comparison of inside and outside temperature suggest that the night cooling effect could be used even more intensively by opening the windows at least 3 hours earlier.

Summer comfort: Thanks to the night ventilation and the shading devices, big overheating

problems were avoided.

Shading devices: The efficacy of the external screens could be increased by an automatic

control instead of manual control.

Night Cooling: For security reasons, windows on the ground floor are not opened at

night no night cooling. Therefore the offices on the ground floor have an appreciable overheating problem in summer.

User behaviour: Closed doors during the night obstruct often the night cooling in summertime. Clear user instructions could help.

A comparison of inside and outside temperature suggest that the night cooling effect could be used even more intensively by opening the windows at least 3 hours earlier.

NatVent










Major findings Major findings (2...)(2...) summer comfortsummer comfort

Night Cooling (optimisation of ventilation & stack effect): The openable area on each floor produced an unequal air change rate

which resulted in a reduced night cooling effect and an increased risk on overheating for the upper floors.

A better analysis of the relation between the opening surfaces and their height above the ground (analysis of the neutral level pressure) can increase the night cooling efficiency.

Night Cooling (optimisation of ventilation & stack effect): The openable area on each floor produced an unequal air change rate

which resulted in a reduced night cooling effect and an increased risk on overheating for the upper floors.

A better analysis of the relation between the opening surfaces and their height above the ground (analysis of the neutral level pressure) can increase the night cooling efficiency.

Pressure diff. linePressure diff. line

BETTER...

NatVent










In Winter: Due to problems with the controls for the heating system

indoor temperatures were too high. Windows are opened to cool the building. This lead to unnecessary ventilation losses. In order to avoid ventilation due to overheating in winter, the heating supplied to the offices on the south-west building side should be reduced significantly especially in the sunny winter afternoons.

The IAQ is acceptable

In Summer: The IAQ is acceptable

In Winter: Due to problems with the controls for the heating system

indoor temperatures were too high. Windows are opened to cool the building. This lead to unnecessary ventilation losses. In order to avoid ventilation due to overheating in winter, the heating supplied to the offices on the south-west building side should be reduced significantly especially in the sunny winter afternoons.

The IAQ is acceptable

In Summer: The IAQ is acceptable

Major findings Major findings (3|)(3|) indoor air qualityindoor air quality

More information...More information...

NatVent










Find more information on the PROBE building in the following documents:

\Reports \Monitoring Reports \Summary Reports\ch1summ.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\ch1det.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\ch1summ.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\ch1det.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

the velux building natvent presentation of the building presentation of the building the design...

Documents