WindowMaster Building

Slide 1:WindowMaster Building

Back to �Select a building� Presentation of the building Ventilation strategy & technology Conclusions WindowMaster office building More information... Summer monitoring Winter monitoring Monitoring set-up Architect of the renovation project: KHR A/S

Slide 2:Building presentation (1...)

Slide 3:WindowMaster: WindowMaster is a company within the VELUX Group WindowMaster is working on the development of electrical and electronic products for the operation and automatic control of windows The office building is located in Vedb�k, about 20 kilometres north of Copenhagen City in a quiet environment. The building: The building, built some 30 years ago, is a factory building renovated in 1995 There are three storeys The basement, only partly below ground, holds various storerooms, workshops and the canteen The offices are on the ground floor and first floor

Building presentation (2...)

Slide 4:Building presentation (3...)

West facade East facade

Slide 5:The west facade with basement, ground floor and first floor.

Building presentation (4...) The east facade with ground floor and first floor.

Slide 6:The entrance, the reception and the main staircase are located in a separate glass construction attached to the west facade of the office building. The doors leading from the staircase to the individual floors are, for security reasons, provided with combination locks and remain closed at all times.

Building presentation (5...) The first floor (the top floor) consists of three open plan offices and a number of cellular offices. Each open plan office has a floor area of about 100 m� and 8 to 12 workplaces.

Slide 7:Of the total floor area of 2.000 m�, some 1.000 m2 (50%) is used for offices and meeting rooms. Offices and meeting rooms are located on the ground floor and first floor. Building materials: The facades of the building are brickwork Roof and horizontal divisions are concrete Internal walls are light gypsum boards and there are light false ceilings The thermal mass of the building can be characterised as medium The building was renovated in 1995. The principal elements in the renovation were exchange of the existing windows with motorised VELFAC windows and a complete renewal of the interior. During the renovation, preparations were made so that in the future fully centralised controls could be installed of all openings in the building with automatic controls for internal solar shading.

Building presentation (6|)

Slide 8:The outdoor air supply in the offices is based on the occupants use of both: 1. ordinary openable windows and 2. smaller openings positioned above these ordinary windows. On the first floor (the top floor) two openable roof lights are provided in order to facilitate air exhaust utilising natural driving forces. The roof lights are located near the staircases. From the ceiling to the roof light there is a short stack. Control of the openings: All openings are equipped with motors. The motors are activated via keypads in control panels located near the windows. At the moment, all openings are controlled by the occupants. The wiring and the low-voltage electrical installations have been designed and laid out so that in the future full centralised automatic control of all openings in the building can be installed.

Ventilation system (1)

Slide 9:Ventilation system (2...)

Roof lights Openable windows Small ventilation glazing above windows The ventilation system is based on cross ventilation & stack effect. Pictures of ventilation devices se next slides ? ...

Slide 10:Ventilation technology (3...) offices

In the offices there are manually operated motorised windows. The actuators are built into the window frames

Slide 11:Ventilation technology (4...) offices

Slide 12:Ventilation technology (5...) roof lights

Slide 13:Ventilation strategy (6...)

At the present time the indoor conditions are not controlled automatically. So control depends on the occupants: Thermal summer comfort The occupants can reduce the risk on overheating by: Ventilating the building intensively by opening the windows (when Text < Tint). However this is only possible during the day: for security reasons, all of the windows in the building close at 18.00 hrs. In theory after 18.00hrs, only the smaller openings above the windows can be operated. When the building is empty a special security system ensures that all windows are closed. Internal Venetian blinds are used to reduce the solar gains. During office hours Indoor Air Quality (in winter and summertime) can be controlled by opening the windows.

Slide 14:Ventilation strategy (7|)

Remark: In addition to providing a comfortable indoor climate, WindowMaster aim to use their building to test their own products and various control strategies. As preliminary test of the system would involve leaving the ventilation openings open for a period of 30 minutes around midnight and also in early morning before the occupants would arrive.

Slide 15:Investigated offices Four offices on the first floor (top floor) were chosen for the monitoring Office 1: 15 m2 cellular office Office 2: 15 m2 cellular office Office 3: 15 m2 cellular office Office 4: 100 m2 open plan office, 8 persons Offices 1 and 2 are facing west, office 3 is facing east. Office 4 is full building depth.

Monitoring set-up Office 4 Office 2 Office 1 Office 3 In the building, smoking is only permitted on the landings in the southern staircase It proved difficult to obtain reliable results from tracer gas measurements in office 4. Therefore, measurements from office 4 comprise exclusively CO, CO2, temperature and relative humidity results

Slide 16:Summer monitoring (1...) Indoor (average of 4 offices) & outdoor temperatures for a three months period

Text. Tint. The internal temperatures are often > 25�C and sometimes > 28�C.

Slide 17:Summer monitoring (2...) results of measurements in office 3

Tint. Air Supply The use of intensive ventilation is quite irregular. However, there is no ventilation at weekend and mostly only limited ventilation at night. weekend Text.

Slide 18:Summer monitoring (3...) results of measurements in office 3

Air Supply weekend Tint. CO2-conc. The air supply during the office hours is very high (intensive ventilation > 20 l/sm�). This leads to very low CO2 -concentration max.550 ppm (= far below the limit concentration of 1200ppm)

Slide 19:Summer monitoring (4...) Questionnaires

In addition to the measurements, the occupants filled in two questionnaires concerning their views on various environmental conditions in their office. One questionnaire concerned the summer season in general and the other concerned one week in particular (in the summer season), namely the one in which the questionnaires were handed out. Each occupant indicated his/her rating of each of the conditions (temperature, air movement etc.) through placing vertical marks on dimensionless, horizontal lines of equal length ranging from most positive (comfortable, fresh etc.) to most negative (uncomfortable, stuffy etc.). The rating is quantified by measuring (in millimetres) the distance along each line from most positive to the occupant�s mark. For practical purposes, the ratings have been converted into the range 0-100. The next slide summarises the ratings concerning the summer season in general.

Slide 20:Summer monitoring (5...) Questionnaires

Slide 21:Thermal summer comfort: During a two week period in the month of August, the indoor temperature (average of simultaneous recordings in four offices) was constantly above 25�C. On extreme days the indoor temperature peaked close to 30�C. Nevertheless, generally acceptable room temperatures are found during a greater part of the summer. The summer comfort could be further improved by: ventilating the building during the night to cool down the thermal mass installing an (automatically controlled) external shading devices (instead of internal blinds) CO2 level and mean air velocity are well below critical limits. The overall picture obtained from the questionnaire is that the occupants are generally satisfied with the indoor environment.

Summer monitoring (6|) Findings

Slide 22:Winter monitoring (1...) Indoor (average of 4 offices) & outdoor temperature during a two months period

Text. Tint. The internal temperatures are between 18 - 22�C All windows open by mistake

Slide 23:Winter monitoring (2...)  results of measurements in office 2

Air supply. Indoor CO2-conc. The air supply during the office hours is sufficient ? On the whole the IAQ is acceptable (CO2 -conc. generally below 1200ppm.). The air supply outside office hours is not zero, due to test (see further �) Tint.

Slide 24:Winter monitoring (3...) Questionnaires

In addition to the measurements, the occupants filled in two questionnaires concerning their views on various environmental conditions in their office. One questionnaire concerned the winter season in general and the other concerned one week in particular (in the winter season), namely the one in which the questionnaires were handed out. Each occupant indicated his/her rating of each of the conditions (temperature, air movement etc.) through placing vertical marks on dimensionless, horizontal lines of equal length ranging from most positive (comfortable, fresh etc.) to most negative (uncomfortable, stuffy etc.). The rating is quantified by measuring (in millimetres) the distance along each line from most positive to the occupant�s mark. For practical purposes, the ratings have been converted into the range 0-100. The next slide summarises the ratings concerning the winter season in general.

Slide 25:Winter monitoring (4...) Questionnaires

Slide 26:The winter indoor climate can be considered as comfortable: During occupancy the indoor temperature in the offices reached about 22 �C, the CO2 concentration 800-1000 ppm and in office 2, given here as an example, the outdoor air supply equalled air change rates of 2-5 times per hour during the office hours. Normally the ventilation rate is zero outside the office hours (to reduce energy losses). During the measurements WindowMaster tested a control strategy which included opening of the windows at midnight for 30 minutes. One effect, which can be seen from the charts, is that the CO2 concentration is at its minimum just after midnight. Indications are given that the occupants rated the indoor environment to be more on the comfortable side in the winter-time than in the summer-time.

Winter monitoring (5|) Findings

Slide 27:Findings from summer-time monitoring Thermal summer comfort: During a two week period in the month of August, the indoor temperature (average of simultaneous recordings in four offices) was constantly above 25�C. On extreme days the indoor temperature peaked close to 30�C. Nevertheless, generally acceptable room temperatures are found during a greater part of the summer. The summer comfort could be further improved by: ventilating the building during the night to cool down the thermal mass installing an (automatically controlled) external shading devices (instead of internal blinds) The overall picture obtained from the questionnaire is that the occupants are generally satisfied with the indoor environment.

Conclusions (1...)

Slide 28:Findings from winter-time monitoring The winter indoor climate can be considered as comfortable: During occupancy the indoor temperature in the offices reached about 22 �C, the CO2 concentration 800-1000 ppm and in office 2, given here as an example, the outdoor air supply equalled air change rates of 2-5 times per hour during the office hours. Normally the ventilation rate is zero outside the office hours (to reduce energy losses). During the measurements WindowMaster tested a control strategy which included opening of the windows at midnight for 30 minutes. One effect, which can be seen from the charts, is that the CO2 concentration is at its minimum just after midnight. Indications are given that the occupants rated the indoor environment to be more on the comfortable side in the winter-time than in the summer-time.

Conclusions (2|)

Slide 29:More information...

NatVent Back to �Select a building� Presentation of the building Ventilation strategy & technology Conclusions WindowMaster office building More information... Summer monitoring Winter monitoring Monitoring setup Find more information on the PROBE building in the following documents: \Reports \Monitoring Reports \Summary Reports\dk3summ.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\dk3det.pdf detailed reports of all 19 monitoring campaigns (?20p./campaign) contents: monitoring set up - analysis of results - conclusions