The Benefit of Daylighting functions proves itself to be in all kind of buildings. Earlier on I wrote about the benefit of Daylighting and Task lighting, with the combination of both of this, you get the best management practice for lighting that is economical and yet ergonomically right. But to support it further, this time I will talk about some peer reviews which I extract from David Strong Consulting that describes the benefits of glazing in terms of social and economic.
In his report, there is 4 distinctive categories of buildings mentioned, namely HealthCare Buildings, Workspace, Institutions/Schools, and Retail Buildings. There were studies done in proving how the daylight has been a testimony in many ways it could be, to different occupants in different buildings role.
The Benefits of Daylight in Healthcare
When it comes to designing Healthcare buildings, M&Es are often the most emphasize area as you have different services running through everywhere, but when it comes to daylighting the rooms, it’s widely related to the essential post operation recovery of the patience.
The common impression we have on hospitals is often bright and the importance of landscaping is still not really emphasized. But we could see the importance of Daylighting extensively through several reports and findings here.
1) The Impact of Daylight and Patients ALOS (Average Length of Stay)
“25% of the comparison sets showed that, in the brighter orientations, as in rooms located in the SE area, the average length of stay by patients was shorter than that in the NW area by 16%-41%. Further, no dataset showed a shorter patient ALOS in the NW area than in the SE.
“The high illuminance in the morning seemed to be more beneficial than in the afternoon. Since short ALOS cases were more consistently found in the SE, it would appear that morning light has more positive effect than light in the afternoon does, and provides physiological benefits for human”
Choi JH, Beltran L and Kim H, Impacts of Indoor Daylight Environments on patient average length of stay in a healthcare facility
“ A retrospective study of myocardial infarction patients in a cardiac intensive area unit treated in either sunny rooms or dull rooms found that female patients stayed a shorter time in sunny rooms (2.3 days in sunny rooms, 3.3days in dull rooms).
Joseph A, The impact of Light on Outcomes in Healthcare settings.
2) On Post Operative Recovery
“ The windowless ICU had twice as many patients developing post operative delirium and depression. Windows provided a psychological escape that decreased the stress level for patients. This environment provides a necessary mental balance for patients and reduces the tendency toward brief psychotic episodes. Windows are important in the medical field because they can reduce the stress and depression in patient unit.
Wilson L. Intensive Care Delirium. The effect of outside deprivation in a windowless unit.
3) The importance of views from Healthcare Building
“Twice as many windowless patients demonstrated delirium and, among patients with abnormal haemoglobin or blood urea, the incidence was threefold. Hallucinations were more than twice as high in a new windowless unit than in the old unit.”
Wilson L. Intensive Care delirium; The effect of outside deprivation in a windowless unit.
4) Daylight and Pain Relief
“Consecutive patients undergoing elective spinal surgery who were assigned postoperatively to rooms on either the bright or dim side of the hospital unit. The patients staying on the bright side received 46% more natural sunlight and required 22% less opioid equivalent analgesic medications during their hospilization. The patients staying on the bright side also experienced a 21% reduction in analgesic medication cost compared on the dim side.”
Walch JM, Rabin BS, Day R, Williams JN, Choi K and Kang JD, The effect of sunlight on postoperative analgesic medication usage.
5)Treatment of depression and depressive Illness
“Bipolar depressed inpatients in east facing rooms (exposed to bright light in the morning) stayed an average of 3.67 days less in the hospital compared with similar patients who stayed in west facing room.”
Benedetti and Colleague (2001). Morning sunlight reduces the length of hospitalization in bipolar depression. Journal of Affective Disorders.
6)Optimum Window Design and Size in Healthcare buildings
“Four factors which influence window design are Sunshine, Awareness, View and Lack of Privacy. Being close to a window was highly desirable regardless of the size of the visual field”
Markus T. The function of Windows. Building Science 1967
“Unpleasant feelings of enclosure were minimal with a window width of at least 1.5 metres. The ideal was two lateral windows with a total width of 3-4 metres in a six metre wide room.
Roessler G. The psychological Function of windows for the visual communication between the interior of rooms with permanent supplementary artificial lighting and the exterior.
“2% of patients and 62% of staff considered sunlight to be a nuisance, while 91% of patients and 31% of staff considered sunlight to be pleasurable. In hospitals, when forced to choose between good views without indoor sunshine and unpleasant views with indoor sunshine, 50% preferred the former while 31% preferred the latter.”
Neeman E. Visual aspect of sunlight in buildings. Light Research and Technology 1974
The Benefits of Daylight in WORKSPACE
The effect of Daylight in the workspace has a lot to do with the psychological aspect of lighting. In earlier post, i mention on how daylighting is better compared to artificial lighting in terms of quality of the light spectrum. But here the findings emphasize on the psychological aspect. Employees did not believe working by electric lighting resulted in poor work output, they believed that their work output was achieved at greater personal STRESS Level.
“The Study reports that 35% of employees when questioned “instantly” identified the absence of a window to be their major concern associated with their office. The reasons are No daylight, Poor ventilation, Inability to see outside and know what is happening, the feelings of being cooped-up, isolation and depression.
Among the respondents, Employees highly value any size of window that they have access to and value it more than privacy in their office.I.96% preferred to work under natural light as opposed to electric lighting.II.86% preferred having sunshine in their office year round.III.74% preferred having a window close to their workspace.IV.57% preferred the window to be beside their workspace rather than in front or behind their workspace.
The Benefits of Daylight in INSTITUTION
The effect of Daylight in Institutions, or educational facilities is widely emphasized on enhancing the productivity and student’s performance. Good Daylight design brings the good environment to health as well, as most students stay indoors for the entire day during their education years. Furthermore, this can be proven by peer reviews proving their increasing performance and also their attendance rate. The Green School in Bali is known for its excellence design that begs many awards, fully made by localized bamboo, this structure of institutional activities offer sufficient daylight and pleasant surrounding landscape view.
Daylight and enhanced student performance
“Student with the most daylighting in their classrooms progressed 20% faster on math tests and 26% on reading test in one year than those with the least. Similarly, students in classrooms with the largest window areas were found to progress 15% faster in math and 23% faster in reading than those with the least. And students that had a well designed skylight in their room, one that diffused the daylight throughout the room and which allowed teachers to control the amount of daylight entering the room, also improved 19-20% faster than those students without a skylight.”
“..Students in classrooms with the most daylighting were found to have 7%-18% higher scores than those in the rooms with the least”
Heschong Mahone GroupDaylighting in Schools. An investigation into the relationship between daylighting and human performance condensed report.
“Summary of good daylighting designs are: An Ample and pleasant view out of window, Source of Glare negatively impact student learning. Direct sun penetrations into the room can cause both glare and thermal discomfort. Blinds and Curtains allow teacher to control the intermittent sources of glare or visual distraction through their windows.”
Hmg, California Energy Commission 2003
Daylight and Health impact
“Full spectrum fluorescent light closely resembles daylight, but it does not provide the same spectral content. The full spectrum fluorescent schools reported that student dental decay decreased nine times [compared to schools with fluorescent lights] as a result of the increase in Vitamin D.Students in the Canadian full spectrum fluorescent schools grew 2.1cm more in two years compared to students who attended traditional fluorescent lit schools. This study also concludes that children under electric light (in which does not have ultraviolet radiation) all day have decreased mental capabilities, agitated physical behavior and fatigue.”
Hathaway, W.E, “A summary of Light Related studies” A Study into the Effects of Lights on Children of Elementary School Age.
School Attendance and Absenteeism
Schools that have integrated full spectrum fluorescent or natural light show an increase in student and teacher attendance when compared to traditionally lit schools. A study of the full spectrum fluorescent Canadian schools reported that students had an attendance increase of 3.2 to 3.8 more days per year than students in traditional fluorescent lighting schools.
Hathaway, W.E, “A summary of Light Related studies” A Study into the Effects of Lights on Children of Elementary School Age
The Benefits of Daylight in RETAIL
The common sighting we see in the shopping malls in Malaysia is fully artificial down lighting, where you don’t see much window openings and everything is mechanical ventilated. Nothing wrong with that as we know that the crowd heat gain is huge and we need M&E to come in, but if you have the chance to visit Citta Mall, at Ara Damansara, so far that’s the preferred neighbourhood mall of mine, where corridor is open air and only individual shop lots have AC kicking in. Anyways, the benefits of daylighting may surprise you too as it increases sales too.
I.“Average effect of daylighting on sales for all daylit stores in this chain was variously calculated at 0% to 6% depending on the type of model and time period considered.”II.A bound with an empirical daylight effect for this chain was detailed, with a maximum effect found in the most favorable stores of about a 40% increase in sales.III.Along with an increase in average monthly sales, the daylit stores were also found to have 1-2% increase in the number of transactions per month.IV.The value of the energy savings from the daylighting is far overshadowed by the value of the predicted increase in sales due to daylighting; by the most conservative estimate of at least 19times.V.The chain studied was found to be saving about USD $0.24/sf per year due to use of photocontrols, which could potentially increase up to USD0.66/sf per year with an optimized daylighting system.
“Positively and significantly correlated to higher sales. All other things being equal, an average non-skylit store in the chain would likely have 40% higher sales with the addition of skylights, with a probably range between 31% and 49%. This was found with 99% statistical certainty. After the number of hours open per week, the presence of skylights was the best predictor of the sales per store of all the variables that we considered. Thus, if a typical non skylit store were averaging sales of $2/sf, then its sales might be expected to increase to between $2.61 and $2.98 with the addition of a skylighting system.”
“The skylights are seen to have a major impact on the overall operation of the chain. Were the chain to add the skylighting system to the remaining 33% of its stores, yearly gross sales are predicted to increase by 11%. The difference between having none of their stores skylit and all their stores skylit is a increase up to 40% in gross sales for the retail chain.”
Pacific Gas and Electric Company/Mahone1999 Skylighting and Retails Sales An investigation into the Relationship between Daylighting and Human Performance.
Personally, I LOVE Sunway Giza a lot. This design isn’t the first in Malaysia, previously was seen in NZX in Ara Damansara which was closed down due to poor proximity and tenants. But yes I just like open air atriums, where people would not feel that hot but yet still get to feel the daylight and the attachment to the nature happening, rain etc. And don’t you think it’s way architectural aesthetic. The Double volume that made it so wide open, unlike thick compact shopping malls with heavy M&E in need.
So yes I hope these peer reviews can help you understand a little bit more on the qualitative aspect of the ergonomic or economical benefits. It’s not all about daylight is better than artificial light due to its “free” source of energy and better lighting characteristic, but let’s just say, I believe these findings have been discovered long ago, ages centuries ago, you can easily find out a lot of interesting facts in the ancient civilizations on how much lighting matter to them, and it’s even in the “building code” they used to have! Ahh shall write about that soon. That’s all for now. So go for daylighting! Common sense!