Tax Office of Enschede S.H. Liem, A.H.C. van Paassen Delft, April 1998 S.H. Liem, A.H.C. van Paassen Delft, April 1998 Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring NatVent

Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation background information The Tax Office of Enschede was completed in It is located near the central railway station. It has offices on 5 floors and a total floor area of 4300 m 2. The building is wedge shaped (see ground plan on next slide ...). It is owned by the Government Building Agency. Design: Architect: ir. Ruurd Roorda, Government Building Agency, NL. Daylight concept: Esbensen, DK. Energy concept & natural ventilation: W/E consultants, NL. Building physics: Peutz & Associes, NL. This building is an EC2000 project, and is very energy efficient (17 m 3 /m 2 gas equivalent of primary energy use) as a result of integrated design. The aim was to eliminate the need for mechanical ventilation and give occupant the maximum possible control of the indoor climate. Key issues are: optimal use of daylight, passive ventilation, cooling by night ventilation, low energy use and use of sustainable building materials.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation typical floor plan (1 st floor) Typical floor plan N Cellular offices Meeting room Cellular offices Storage of files corridor ATRIUM Street + Railway Street Square Connection to old building

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation cross section & view of the atrium Cross section N ATRIUM Cellular office Storage of files Upward view of atrium Internal solar protection

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation view of the atrium & rear façade Downward view of atrium Rear façade

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation ventilation installation Concept: The ventilation system is based on the stack effect of the atrium (see schematic on next slide ...). Installation: Fresh air enters the building via the trickle vents in the office. The air passes to the atrium via acoustic ducts in the false ceiling. The air leaves the building via the roof of the atrium (by natural means). Fan-assisted: If the wind velocity is less than 2 m/s, fans are switched on to help the stack effect in the atrium. Extraction chimneys on the roof Fans for suppl. ventilation

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation ventilation concept - stack effect Trickle vents Acoustical ducts in false ceiling

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation ventilation components 2 Trickle vents in each office Extraction opening of the acoustic duct in the office The settings of the trickle vents are clearly marked: 0: all closed 1: 1 open 2: 2 open Remark: The trickle vents have very high acoustical performances (railway in front of the building). They are also pressure independent: within a certain range, they give the same flow at different pressures (see next slide...  ) The two constant flow trickle vents are situated just below the exposed ceiling. The incoming cold air sticks to the ceiling by the Coanda effect and is mixed with the warm indoor air before it falls into the office space, witch prevents draughts from causing comfort problems.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation pressure independent vents Pressure independent vent Pressure dependent vent Pressure difference:  p (Pa) Flow Q (m³/h) Q design Pressure difference range Pressure independent vents give a constant flow within a range of pressure differences.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation offices Besides the ventilation devices, the offices have other features which improve the indoor climate: External blinds on the South façade to reduce the solar gains and avoid overheating. A shelf beneath each window reflects the daylighting windows reflects the light deep in the room and so improves the light distribution. A high frequent light system keeps the light level at 500 lux. The offices have a lot of exposed thermal mass in the ceilings and tiled floors. Therefore acoustic panels have been installed in the offices to reduce reverberation. All these techniques are presented on the following schematic… 

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation offices

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation shading device on the South façade External view Internal view - open Internal view - closed Daylight shelf with integrated lights Trickle vents Daylighting window Light shelves are automatically controlled by a solar radiation sensor, but it can be manually overruled

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Building presentation the building strategy A desk map gives very clear instructions to the occupants how to use the different devices in winter & summer (see next slide ...) In the winter: Ventilation: during OH: position 1 (for Indoor Air Quality) outside OH: position 0 (to reduce ventilation losses) Heating: during OH: choose adequate level outside OH: keep chosen level Lighting during OH: on, if necessary outside OH: off External shading: during OH: control freely outside OH: automatic control In the winter: Ventilation: during OH: position 1 (for Indoor Air Quality) outside OH: position 0 (to reduce ventilation losses) Heating: during OH: choose adequate level outside OH: keep chosen level Lighting during OH: on, if necessary outside OH: off External shading: during OH: control freely outside OH: automatic control In the summer: Ventilation: during OH: position 1 or 2 (for Indoor Air Quality & intens. vent.) outside OH: position 2 (intensive night ventilation) Heating: during OH: choose adequate level outside OH: keep chosen level Lighting during OH: on, if necessary outside OH: off External shading: during OH: control freely outside OH: automatic control In the summer: Ventilation: during OH: position 1 or 2 (for Indoor Air Quality & intens. vent.) outside OH: position 2 (intensive night ventilation) Heating: during OH: choose adequate level outside OH: keep chosen level Lighting during OH: on, if necessary outside OH: off External shading: during OH: control freely outside OH: automatic control

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Winter Summer During office hours Outside office hours During office hours Outside office hours ventilation heating lighting External shading Internal shading Desk map with user instructions

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Monitoring the monitoring scheme A winter (April) and summer (September) survey was organised. In April the Coanda effect was determined in rooms 111, 121, 314, 320, 503 and 520; the CO 2 levels were measured in rooms 105, 123, 505 and 518. In June and July summer ventilation rates and CO 2 levels were monitored in rooms 107, 122, 311, 322, 505 and 520. The whole year the indoor temperature was monitored. A winter (April) and summer (September) survey was organised. In April the Coanda effect was determined in rooms 111, 121, 314, 320, 503 and 520; the CO 2 levels were measured in rooms 105, 123, 505 and 518. In June and July summer ventilation rates and CO 2 levels were monitored in rooms 107, 122, 311, 322, 505 and 520. The whole year the indoor temperature was monitored.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Winter monitoring questionnaires 170 questionnaires were distributed. 102 are returned. Of the respondents 20% are female and 80% male, the average age is 42 years. Main results: They showed that temperatures in the offices were good, with enough possibilities to control it. Air movement was reported to be either ‘adequate’ or ‘too high’.The amount of control available to the occupants was either acceptable or good. Air quality was ‘adequate’ and humidity either ‘good’ or to ‘low’. Unpleasant odours from cigarette, office equipment and diesel fumes were considered to ‘acceptable’ by 75% of the respondents and ‘not’ acceptable by the remaining 25%. 96% are pleased with the daylighting, 58% complain about glare 99% have sufficient artificial light, 88% have control over the light levels The noise level is ‘good’ to ‘satisfactory’ -10% of the interviewees persons have problems with the noise. 170 questionnaires were distributed. 102 are returned. Of the respondents 20% are female and 80% male, the average age is 42 years. Main results: They showed that temperatures in the offices were good, with enough possibilities to control it. Air movement was reported to be either ‘adequate’ or ‘too high’.The amount of control available to the occupants was either acceptable or good. Air quality was ‘adequate’ and humidity either ‘good’ or to ‘low’. Unpleasant odours from cigarette, office equipment and diesel fumes were considered to ‘acceptable’ by 75% of the respondents and ‘not’ acceptable by the remaining 25%. 96% are pleased with the daylighting, 58% complain about glare 99% have sufficient artificial light, 88% have control over the light levels The noise level is ‘good’ to ‘satisfactory’ -10% of the interviewees persons have problems with the noise.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Winter monitoring the Coanda effect The Coanda effect causes the flow of cold air to stick to the ceiling for a long enough period for it to mix with the warm indoor air before it falls into the space below. This prevents discomfort from draughts. The table below shows the number of times this phenomenon was detected and the distance travelled by the cold air before it fell into the space bellow. The only room in which the Coanda effect was not noticeable was number 503 on the South façade of the 5th floor. The Coanda effect causes the flow of cold air to stick to the ceiling for a long enough period for it to mix with the warm indoor air before it falls into the space below. This prevents discomfort from draughts. The table below shows the number of times this phenomenon was detected and the distance travelled by the cold air before it fell into the space bellow. The only room in which the Coanda effect was not noticeable was number 503 on the South façade of the 5th floor.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Winter monitoring ventilation In the winter only one trickle vent is open. The aim is to get a ventilation flow of 100 m 3 /h (2 ach). The table below shows the results of experiments carried out on April 16 th. During the period monitored, the wind was from the North with a velocity of 2 m/s. The outdoor temperature was 10°C. These values are close to the design conditions for the building. Air flow rates measured on the 3 th and 5 th floors are within 10% of each other; air flow rates on the 1 st floor are rather high due to some construction problems. These problems have since been resolved. In the winter only one trickle vent is open. The aim is to get a ventilation flow of 100 m 3 /h (2 ach). The table below shows the results of experiments carried out on April 16 th. During the period monitored, the wind was from the North with a velocity of 2 m/s. The outdoor temperature was 10°C. These values are close to the design conditions for the building. Air flow rates measured on the 3 th and 5 th floors are within 10% of each other; air flow rates on the 1 st floor are rather high due to some construction problems. These problems have since been resolved.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Winter monitoring CO 2 concentration level The outdoor CO 2 concentration level is 350 ppm. Values less than 350 ppm are due to the accuracy of the measurement apparatus that is used. The CO 2 concentration levels found in the rooms are well below the maximum level of 1500 ppm; even CO 2 concentration levels of 1200 ppm are very rare.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Summer monitoring questionnaires Of the 170 questionnaires that were distributed, 105 were returned. 19% of the respondents were female and 81% male, the average age was 42 years. The survey was held in September, just after the ‘heat wave’ in August which clearly influenced the results. Main results: The temperature on the workplace were ‘very hot ‘, control ‘bad’, very little ventilation with ’bad’ ventilation control, although control of draughts was adequate. The air quality is ‘satisfactory’ and the humidity ‘good’. 50% experience ‘smelly’ air, 60% blames this on the nearby railway station; for 55% this was acceptable and for 45% not acceptable. 99% were ‘satisfied’ with the illumination, 3% wanted more light, 94% could sufficiently control the day lighting, 35% had some problems with glare on their computer screen. 98% had sufficient electric light and can control it. Although the noise level was acceptable, 12% had problems with it. Of the 170 questionnaires that were distributed, 105 were returned. 19% of the respondents were female and 81% male, the average age was 42 years. The survey was held in September, just after the ‘heat wave’ in August which clearly influenced the results. Main results: The temperature on the workplace were ‘very hot ‘, control ‘bad’, very little ventilation with ’bad’ ventilation control, although control of draughts was adequate. The air quality is ‘satisfactory’ and the humidity ‘good’. 50% experience ‘smelly’ air, 60% blames this on the nearby railway station; for 55% this was acceptable and for 45% not acceptable. 99% were ‘satisfied’ with the illumination, 3% wanted more light, 94% could sufficiently control the day lighting, 35% had some problems with glare on their computer screen. 98% had sufficient electric light and can control it. Although the noise level was acceptable, 12% had problems with it.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Summer monitoring hot period in the summer Due to the external venetian blinds on the south façade and the use of night cooling the internal temperatures are never higher than 28°C during a hot period (Text. = 32°C) :0012:000:0012:000:0012:000:0012:000:00 Time in hours / 11 to 14 August Temperature [°C] Text. Tatrium T room123,North T room127, South

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Summer monitoring Night ventilation The average long term ventilation flow during the last two weeks of July w has been determined in rooms 107, 122, 505 and 520 with the PFT-method. A different tracer gas was used in each room. The gas concentration was measured at different locations in the rooms. Based on these results the ventilation rate was determined. For night time ventilation cooling a minimum ventilation rate of 4 ach or 200 m 3 /h per room is required. The occupants are instructed to open both trickle vents when they go home (= setting 2). The results are: The average summer night ventilation rate is 3.75 ach, the aim is 4 ach. The rooms are flushed very well; there are no ‘dead angles’ with higher concentrations. Leaks between adjacent rooms are small (average 2 -8 m 3 /h, max. 40 m 3 /h in the lower floors and the N-room of the fif th floor). The average long term ventilation flow during the last two weeks of July w has been determined in rooms 107, 122, 505 and 520 with the PFT-method. A different tracer gas was used in each room. The gas concentration was measured at different locations in the rooms. Based on these results the ventilation rate was determined. For night time ventilation cooling a minimum ventilation rate of 4 ach or 200 m 3 /h per room is required. The occupants are instructed to open both trickle vents when they go home (= setting 2). The results are: The average summer night ventilation rate is 3.75 ach, the aim is 4 ach. The rooms are flushed very well; there are no ‘dead angles’ with higher concentrations. Leaks between adjacent rooms are small (average 2 -8 m 3 /h, max. 40 m 3 /h in the lower floors and the N-room of the fif th floor).

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Summer monitoring CO 2 concentration level The CO 2 concentration level during working hours in the summer were measured in June. These results differ not much from the CO 2 level in the winter. The outdoor CO 2 concentration level is 350 ppm. Values less than 350 ppm are due to the accuracy of the measurement instrument. The CO 2 concentration levels found in the rooms are well below the maximum level of 1500 ppm.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Summer monitoring Weighted temperature exceeding hours ISO 7730 describes a method for the evaluation of the internal summer comfort: This is the method of weighted exceeding hours. All hours with a temperature above 25°C are taken into account. High temperatures have a higher weighting factor: Temperature weighting factor 25°C:1.0 26°C:1.4 27°C:2.0 28°C:2.6 29°C:3.4 30°C:4.2 The allowable norm weighted temperature exceeding is 150 degree hours. ISO 7730 describes a method for the evaluation of the internal summer comfort: This is the method of weighted exceeding hours. All hours with a temperature above 25°C are taken into account. High temperatures have a higher weighting factor: Temperature weighting factor 25°C:1.0 26°C:1.4 27°C:2.0 28°C:2.6 29°C:3.4 30°C:4.2 The allowable norm weighted temperature exceeding is 150 degree hours. Based on the monitored indoor temperatures in 1997, 166 degree hours were calculated. These results are not corrected for unintended accidents (opening the windows when it is very hot, cleaning the sun shades during hot summer days, operating the boiler, etc). When corrected, the exceeding is 86 degree hours : the internal summer comfort can be considered as acceptable Based on the monitored indoor temperatures in 1997, 166 degree hours were calculated. These results are not corrected for unintended accidents (opening the windows when it is very hot, cleaning the sun shades during hot summer days, operating the boiler, etc). When corrected, the exceeding is 86 degree hours : the internal summer comfort can be considered as acceptable

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Conclusions - 1 Natural ventilation: The average winter ventilation rate is 2 ach, which was the design intention. Summer night time ventilation rate is 3.75 ach. Indoor Air Quality: The CO 2 levels in summer and winter are always below the maximum value of 1500 ppm. IAQ is of an acceptable standard. The Coanda effect was investigated and it was only in the most unfavourable room, situated on the fif th floor on the lee of the building that this phenomenon was not detected. In all the other rooms it functions well and there are no draught problems. Overall conclusion: the concept of natural ventilation with constant flow trickle vents, acoustic ducts to the atrium and auxiliary fans in the exhaust openings operates well. Natural ventilation: The average winter ventilation rate is 2 ach, which was the design intention. Summer night time ventilation rate is 3.75 ach. Indoor Air Quality: The CO 2 levels in summer and winter are always below the maximum value of 1500 ppm. IAQ is of an acceptable standard. The Coanda effect was investigated and it was only in the most unfavourable room, situated on the fif th floor on the lee of the building that this phenomenon was not detected. In all the other rooms it functions well and there are no draught problems. Overall conclusion: the concept of natural ventilation with constant flow trickle vents, acoustic ducts to the atrium and auxiliary fans in the exhaust openings operates well.

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Cooling by natural ventilation (Night cooling) The ventilation rate for cooling (3,75 ach) is close to the desired value of 4 ach. Higher cooling effects can be obtained if the auxiliary fans are switched on earlier. Indoor temperatures are sometimes higher than would normally be the case because of operator error: (the boiler was switched on in the summer, several sunny days the sun shades were moved so that windows could be cleaned and windows were left open on days when outside temperature was higher than indoor temperature, etc.). There were complains about summertime temperatures, but a heat wave in august had a significant influence on the findings. The uncorrected weighted temperature exceeding is 166 hours for 1997 (an extreme hot year). This value is slightly higher than the limit value of 150 (for a normal year). However when one takes into account operating errors, the value can be lowered to 86 hours. Hence the summer comfort levels can be within acceptable limit if mistakes are avoided. Cooling by natural ventilation (Night cooling) The ventilation rate for cooling (3,75 ach) is close to the desired value of 4 ach. Higher cooling effects can be obtained if the auxiliary fans are switched on earlier. Indoor temperatures are sometimes higher than would normally be the case because of operator error: (the boiler was switched on in the summer, several sunny days the sun shades were moved so that windows could be cleaned and windows were left open on days when outside temperature was higher than indoor temperature, etc.). There were complains about summertime temperatures, but a heat wave in august had a significant influence on the findings. The uncorrected weighted temperature exceeding is 166 hours for 1997 (an extreme hot year). This value is slightly higher than the limit value of 150 (for a normal year). However when one takes into account operating errors, the value can be lowered to 86 hours. Hence the summer comfort levels can be within acceptable limit if mistakes are avoided. Conclusions - 2

NatVent Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Back to “Select a building” Back to “Select a building” Winter monitoring Winter monitoring Summer monitoring Summer monitoring Concluding remarks This concept shows that the integral approach of natural ventilation, effective solar shading, daylight control and the use of thermal mass for heat accumulation leads to a successful application of natural ventilation. Concluding remarks This concept shows that the integral approach of natural ventilation, effective solar shading, daylight control and the use of thermal mass for heat accumulation leads to a successful application of natural ventilation. Concluding remarks and acknowledgement Acknowledgement We thank the Government Building Agency, East Directorate, Arnhem, NL, and W/E consultants sustainable building, Gouda, NL, who has performed the monitoring, to allow us to make use of the data (W/E report , March 1998) and pictures.

More information... NatVent Back to “Select a building” Back to “Select a building” Presentation of the building Presentation of the building Monitoring set-up Monitoring set-up Conclusions Tax Office of Enschede Tax Office of Enschede More information... More information... Winter monitoring Winter monitoring Summer monitoring Summer monitoring Find more information on the PROBE building in the following documents: \Reports \Monitoring Reports \Summary Reports\nl3summ.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\nl3det.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\nl3summ.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\nl3det.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: 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: OR run the installation file ar32e301(1).exe in the directory \Installation