I assessed the suitability of the environmental conditions surrounding level 3 of the Student Union building. When assessing the environmental conditions in the student union building for the first time, it was not the best representation of the space on a day to day basis as there were a large number of student there assessing the environmental conditions as I was. Therefore my observations and measurements could be slightly skewed. However I did come back on multiple other days to get a variety of observations, although my measurements were all from one day only.
The space is mainly used as a thoroughfare for students getting from lecture to lecture. There is a large open staircase that runs up to the third floor from the second floor. Most people using the space come in from the doors on the second floor and walk up the stairs and out through the doors into the Tim Beaglehole courtyard. Along one side of the stairs is the lift, office space and a kitchen for students to use, while the other side leads out onto a rooftop deck. The main space has a high ceiling and 3 out of 4 walls are pretty much all glass windows.
For my assessment I have chosen to just look at the environmental conditions of the main space in which the stairway runs through and not the smaller rooms attached to this space, however I have in some cases, discussed the effects of some of the features of these rooms have, on conditions in the main space.
Other than the main usage as a thoroughfare, the space is also occasionally used by students to sit and study or eat their lunch.
Air quality:
From my initial observations the air appeared fresh. This is due to doors at top of building being open allowing air flow. As a result of the door opening at top of building there is a slight draught which also fluctuates when people simultaneously open the doors at the bottom of building to walk in. However there are two set of doors at both points which reduces the draught so that it is not annoying. There didn’t appear to be any major potential sources of pollutants to the air quality. There is a rubbish bin at the top of the stairs, however it is emptied frequently so doesn’t produce any smell and therefore having very little effect on the quality of air. There are also microwaves in the building that are used by students to heat up food, sometimes the food has a smell that effects the air freshness but due to ventilation in the building these smells don’t hang around long so it is not much of an issue either.
Outdoor CO2 levels are usually 350-450ppm and the maximum indoor air CO2 level considered acceptable is 1000ppm (Kilpatrick, 2014). CO2 levels exceeding 1000ppm suggest that there is inadequate ventilation in a building (NIOSH, 2017). The air quality that I measured in the space was an average of 400 units of CO2. When compared to the acceptable amount of CO2 this appears very low which means that the level of CO2 is on par with the outdoor CO2 level resulting in a well ventilated space.
It is important to have a high level of air quality inside a space used for human occupation. If CO2 levels are too high, it can result in discomfort for users with symptoms such as drowsiness, headaches and lower activity levels. Because this is a space for students, these are effects that we don’t want to be experiencing therefore it is very important that the amount of CO2 in the air is acceptable. In saying this it is also important not to over ventilate as producing a surplice amount of fresh air is wasting energy which is not a sustainable action.
When I took my measurements and observations it was a sunny mild day so the doors were open. It was not a time between lectures so there were not that many people walking through the building. I would expect the CO2 levels to be higher in-between lecture times as there are a lot more people walking through then which I noticed when I came back to make more observations another time. I would also expect the air quality to decrease on rainy cold days as the doors would be kept shut decreasing the amount of air flow through the space as well as there being more people inside due to the rain outside causing the CO2 levels to increase. However because the CO2 level that I measured was significantly below the maximum acceptable CO2 level, I would still expect the air quality to be under this value on heavier traffic days. There are no HVAC ducts directly in the space I was looking at, however the whole interior space is fairly open so the HVAC ducts in the atrium would also service level 4. These would help with ventilation on days where the doors are not open as there don’t appear to be any opening windows in the space. Overall the space is well ventilated and has a good level of air quality.
Thermal:
Thermal comfort is important and according to the Health and Safety in Employment Act 1992, heat and cold stress is a “significant hazard”, and that heat and cold strain can cause “serious harm” (Health and Safetly in Employment Act 1992, 2016).
The temperatures that I measured when I was there on a very sunny day was a ground temperature of 28.9 degrees Celsius and a ceiling temperature of 29.5 degrees Celsius. The dry temperature was 23degrees and the wet temperature 15degrees Celsius. The relative humidity was 42%. The recommended indoor temperature is around 21 degrees Celsius (Greenage, 2018) making the temperature of the building higher than the recommended. Indoor humidity levels should be below 50%. Maintaining relative humidity prevents dust mite infestations, mold and mildew growth and inhibits bacteria. In winter humidity levels must be lower, around 30-40%, to prevent condensation on windows and other surfaces (Therma-Stor, 2018). High RH (relative humidity) makes people feel chilled in cold weather, and hot and sticky in warm weather whereas low RH can cause dryness and discomfort in the nose and make skin dry and itchy (Level, 2017). Therefore it is very important that the RH is just right. The RH inside the Student Union is within the comfortable range which was evident when I was inside the building.
From my observations I noticed that it was noticeably warm due to sun radiating in through all the glass windows of the building however it wasn’t unpleasant when I was walking though only when I sat down for a while on the seating along the window facing the deck. This was where it appeared to be especially hot. The stairs are cooler because they are in line with the open door at the top, so the cool wind blowing in made the temperature more manageable. The temperature inside the building would definitely be effected by the different climatic conditions outside. It would be very hot on sunny windless days as 3 out of 4 walls are mainly glass allowing lots of sunlight to radiate in. On days where there is no sun I would expect the temperature to drop significantly due to lack of sunlight radiating in. More people in the building would also increase the temperature making it less pleasant to be in.
Visual:
I measured an indoor horizontal lux of 290 and a vertical lux of 630.
I observed that is was easy to see things that needed to be seen on the day that I was there. The building is very sufficiently lit as a result of the large glass walls encompassing the space. Due to this large amount of glass, on the sunny day that I visited I noticed that it was actually rather glary. It made it hard to do any work on my laptop or paper when I was sitting by the large glass window. However I would not consider this place to be designed or used as a place for study so that is okay. On overcast days the sun would not light up the space so there is large lights on the ceiling that will sufficiently light the space.
It is best to avoid direct sunlight and skylight which create excessive brightness differences especially on critical tasks which makes this space fairly un useable for study during bright sunlight hours. Things that could be done to filter the direct daylight is with trees and plants outside the windows or screens.
Acoustics:
My measurement for the sound levels in the space were 76.7dbA inside next to the speaker. 53.5dbA in the quietest place. The average inside was 58.9dbA on the slow response and 70.6dbA on the fast response. The outside measurement were also very similar, however I would say there were quite a lot of people outside compared to normal and it wasn’t peak time inside when I made these measurements. From my observations it was very easy to hear people, however when I went back to the space on a busier day I definitely had to raise my voice a bit as there were a lot of talking as I walked through. When people walk through they are talking generally, this creates a lot of noise which echoes through the space because surfaces are very hard in the space and they do not absorb sound very well resulting in a lot of reverberation. I could not hear any external noises on either of my visits to the space. The windows are not double glazed which effects the amount of sound that can get through so if there were loud noises outside it would be possible to hear this sounds quite well from the inside which could be disturbing to users of the space. Noise can be heard from the floors below because they are all open however it was just general chit chat which is not very disruptive or unpleasant. Normal conversation is about 60dB and sounds above 85dB are considered harmful (Healthwisestaff, 2017). On a busy time I would expect the dB to be higher but not high enough that it is harmful.