DAYLIGHTING STUDIES 1
STUDY OBJECTIVES STUDY OBJECTIVES Light Levels Glare/Uniformity Heat Gain SIMULATION Daylight Autonomy (annual) & Illuminance (point-in-time) Illuminance and Glare Irradiation/Radiation Maps OUTPUT False-color grids False-color grids and images False-color grids and images 2
SIMULATION PARAMETERS WEATHER FILE PRI_Mayaguez-Eugenio.Maria.de.Hostos.AP.785145_TMY3 MATERIALS Ground Concrete Walls Half-Walls Screens Glazing Troughs Furniture Structure Trusses 20% Reflectance 20% Reflectance 50% Reflectance 50% Reflectance 50% Reflectance 20% Visual Transmittance Translucent 20% Visual Transmittance Translucent 50% Reflectance 20% Reflectance 50% Reflectance TARGET ILLUMINANCE LEVEL 3
IS THERE ENOUGH DAYLIGHT? DAYLIGHT AUTONOMY TARGET THRESHOLD 500 LUX Daylight Autonomy (DA) is the percentage of the occupied time of the year when a point in the space receives at least the chosen level of light. DA 25 DA 50 For example, if the threshold level is set to 300 lux, and one calculation node gets a DA of 50 means that 50 percent of the year, the area represented by that node will recieve at least 300 lux of daylight illumination. In this test, we are getting good results. We can see that most of the area is in the yellow or green range meaning that in general the space gets 500 lux of illuminantion between 25 and 50 percent of the year. Nevertheless, supplemental electric lighting will be necessary for patient 4
IS THERE ENOUGH DAYLIGHT? SOUTH FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX DA 25 DA 50 Sesor Grids - Plan Sesor Grids - Elevation 5
IS THERE ENOUGH DAYLIGHT? NORTH FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX DA 25 DA 50 Sesor Grids - Plan Sesor Grids - Elevation 6
IS THERE ENOUGH DAYLIGHT? EAST FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX DA 25 DA 50 Sesor Grids - Plan Sesor Grids - Elevation 7
IS THERE ENOUGH DAYLIGHT? WEST FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX DA 25 DA 50 Sesor Grids - Plan Sesor Grids - Elevation 8
SHOULD THE SKYLIGHT TROUGHS BE MODIFIED? This study of the light levels on the Summer Solstice shows areas under the water collection system are dramatically overlit (shown in pink), due in a large part to the glazing that makes up the troughs. Underlit: <300 lux Well Lit: 300-2000 lux Overlit: >2000 lux 9
SHOULD THE SKYLIGHT TROUGH DESIGN BE MODIFIED? ILLUMINANCE, SUMMER SOLSTICE This study focused on the daylighting conditions during the summer of the areas directly below the glazed water collection system. As we can see, the areas under the skylight troughs are dramatically overlit (shown in pink), due in a large part to the glazing that makes up the troughs. Underlit: <300 lux Well Lit: 300-2000 lux Overlit: >2000 lux Summer Solstice 9am Summer Solstice 12pm Summer Solstice 3pm 10
SHOULD THE GLAZING TYPE OF THE TROUGHS BE MODIFIED? ILLUMINANCE, SUMMER SOLSTICE @ 12PM In this simulation we experimented with changing the glazing type of the skylight troughs from a clear glass to either a 20% translucent glazing, or an opaque material with an 80% reflectance. Underlit: <300 lux Well Lit: 300-2000 lux Overlit: >2000 lux 20% Translucent 80% Reflectance (No Transparency) 11
SHOULD THE EAST FACING FACADE PANELS BE MODIFIED? ILLUMINANCE, SUMMER SOLSTICE This study of the light levels on the Summer Solstice shows areas under the water collection system are dramatically overlit (shown in pink), due in a large part to the glazing that makes up the troughs. Underlit: <300 lux Well Lit: 300-2000 lux Overlit: >2000 lux 12
SHOULD THE EAST FACING FACADE PANELS BE MODIFIED? ILLUMINANCE, SUMMER SOLSTICE @ 9AM The orignal test of the illuminance in the space at 9am was done with wall panels with a 50% reflectance, as opposed to screens or transparent materials. This study was done to see whether it would be better to make the East-facing panels more transparent. Underlit: <300 lux Well Lit: 300-2000 lux Overlit: >2000 lux 50% Reflectance (Opaque) 40% Transmission Glazing 40% Open Screen 13
IS THERE TOO MUCH DAYLIGHT ON THE PATIENT S FACES? SOUTH FACING VERTICAL WALLS @ PATIENT BEDS ILLUMINANCE, SUMMER SOLSTICE @ 9AM Sesor Grids - Plan Sesor Grids - Elevation 14
IS THERE TOO MUCH DAYLIGHT ON THE PATIENT S FACES? NORTH FACING VERTICAL WALLS @ PATIENT BEDS ILLUMINANCE, SUMMER SOLSTICE @ 9AM Sesor Grids - Plan Sesor Grids - Elevation 15
IS THERE TOO MUCH DAYLIGHT ON THE PATIENT S FACES? EAST FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX Sesor Grids - Plan Sesor Grids - Elevation 16
IS THERE TOO MUCH DAYLIGHT ON THE PATIENT S FACES? WEST FACING VERTICAL WALLS @ PATIENT BEDS DAYLIGHT AUTONOMY 500 LUX Sesor Grids - Plan Sesor Grids - Elevation 17
IS GLARE AN ISSUE IN THE MORNING THROUGHOUT THE YEAR? EAST FACADE DAYLIGHT GLARE PROBABILITY (DGP), WINTER & SUMMER SOLSTICES @ 9AM Unlike the West facade, the East facade is not protected by any neighboring buildings, and is therefore susceptible to potentially disabling glare in the morning. In order to determine the risk of glare on the East facade, we tested the daylighting of a 40% open screen using a luminance-based metric called DGP or Daylight Glare Probability. DGP determines the likelihood that an occupant would describe a particular view at a particular time as glary. The metric, based on acutal human evaluations of spaces has four levels: Imperceptible < 35% Perceptible 35% & < 40% Disturbing 40% & < 45% Intolerable 45% Winter Solstice @ 9am Intolerable Glare (DGP 46%) Summer Solstice @ 9am Disturbing Glare (DGP 42%) 18
HOW DOES AN OPEN SCREEN PERFORM IN LOW SUN ANGLES? EAST FACADE DAYLIGHT GLARE PROBABILITY (DGP), WINTER SOLSTICE 9AM - 1PM Since the open screen was preferred by the design team, we wanted to test when under what period of time glare would be problematic for the east-facing beds if open screens were used. Glare is intolerable at 9am when the sun is almost perpendicular to the facade. As the sun moves towards the south, the DGP decreases to levels graded at perceptible. 9am Intolerable Glare (DGP 46%) 10am Perceptible Glare (DGP 39%) 11am Perceptible Glare (DGP 38%) At 12pm however, the DGP spikes up again as the sun peaks through the upper, clerestory portion of the roof. From this we can conclude that it would be desireable to reorient the roof to avoid the glare and heat gain during these times of the day, especially if no other design changes were made. 12pm Intolerable Glare (DGP 45%) 1pm Imperceptible Glare (DGP 34%) 19
MATERIAL OPTIONS FOR EAST FACADE EAST FACADE DAYLIGHT GLARE PROBABILITY (DGP), WINTER SOLSTICE @ 9AM While the screen facade was preferred, we wanted to see the effect of other material options on visual comfort. We tested out an opaque panel with 50% reflectance, a 40% transmissive glazing, and compared it to the 40% open screen. From the tests it is apparent that while the opaque panel will help during the most offensive hours of the day, it will blcok the view during the rest of the time, and will reduce overall light in the space. The translucent panel does not help in reducing glare at all. 40% Open Screen DGP 46% INTOLERABLE GLARE 50% Reflectance (No Transparency) DGP 38% PERCEPTIBLE GLARE 40% Transmission (Glazing) DGP 46% INTOLERABLE GLARE Since the open screen is preferred, further study will be needed to determine the desired openness factor, less than 40%. 20
RECOMMENDATIONS OVERALL Reorient these peaks to avoid glare in late morning/noon, or consider at different glazing or screen treatment Apply louvers or a shading device to minimize heat gain and glare Consider a screen with an opening less than 40%, or additional retractable shading options to avoid glare 21