Guideline to Daylight Simulations in LightStanza with MicroShade. Simulation of MicroShade in LightStanza. About MicroShade.

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1 Guideline to Daylight Simulations in LightStanza with MicroShade This is a guideline to daylight simulations with MircoShade in LightStanza. LightStanza is an advanced web-based simulation software for simulating daylight in buildings. LightStanza is developed by Light Foundry, LLC. This guideline shows how to use MicroShade in LightStanza for simulation of daylight in a building. For further questions regarding LightStanza simulations, please contact LightStanza support at support@lightstanza.com. For questions regarding MicroShade, please contact us at support@microshade.dk. Simulation of MicroShade in LightStanza About MicroShade MicroShade is a highly effective shading product containing microscopic shading lamellas. The shading efficiency depends on the incidence angle of the sun on the lamellas. When the sun is high in the sky during the summer, MicroShade provides the strongest shading and during winter when the sun is low more heat is allowed into the building. Similarly, the shading efficiency also varies during the day due to the different positions of the sun morning, noon and evening. Daylight metrics It is recommended to use either spatial Daylight Autonomy (sda) or Useful Daylight Illuminance (UDI) as the evaluation metric when simulating daylight conditions in a room or building. LightStanza can calculate both daylight metrics under the Annual Grid Illuminance. sda describes the percentage of floor area that receives daylight above a limit, usually 300 or 500 lux, for at least 50% of the annual occupied hours (LEED) or annual daylight hours (EN 17037). UDI describes how many hours, workhours or percentage of the year where the daylight levels are within the desired interval (usually lux). Lower illuminance levels require artificial light and higher illuminance levels causes a risk of overheating and glare. About LightStanza LightStanza is a browser- and cloud-based daylight simulation tool. It is the fastest Radiance-based tool on the market and can perform several types of daylight simulations, both annual (5-phase method) and specific point in time calculations. The calculations can be performed with standard CIE sky conditions, with annual weather data choosen from the location or your own weather data in epw format for proof of regulations. The great advantage of using LightStanza is the fast simulation time and that multiple simulations can be performed simultaneously in the cloud, without having to install the tool on your computer. MicroShade is implemented in the LightStanza software and can be selected under the materials library.

2 Usage BSDF (Bi-Directional-Scattering-Function) files of MicroShade have been developed together with the Laboratory of Performance-Integrated Design at EPFL in Lausanne Switzerland. The models have been validated against angle dependent transmittance measurements. BSDF files of the different MircoShade types are available in LightStanza. For façade applications two MicroShade product types are commonly used MicroShade MS-A and MS-D. Aesthetically, they are similar, but MS-D provides a stronger shading whilst MS-A allows more daylight inside. For roof applications, MS-RS and MS-RW are typically used. MS-RS is recommended in pitches up to 30, and MS-RW is recommended for pitches between 30 and 60. For more information on selection of MicroShade please see our selection guidelines For automatic selection of MicroShade type in LightStanza the following materials are available: 2-layer MicroShade 3-layer MicroShade MicroShade Film only The MicroShade film only option should only be used in case a custom-made glazing is desired, as it requires a specific build-up of the 3D model. Please see action 4. under Applying MicroShade to the project in this guideline. Based on the orientation and tilt of the window, the following MicroShade products will be chosen automatically: 2-layer glazing 4 mm Planiclear + 16 mm Argon + 4 mm Planitherm XN 3-layer glazing 4 mm Planiclear + 16 mm Argon + 4 mm Planitherm XN + 12 mm Argon + 4 mm Planitherm XN North and South facing facades -> MS-A East and West facing facades -> MS-D Roof with pitches below 30 -> MS-RS Roof with pitches between 30 and 80 -> MS-RW After a simulation has been performed, it is possible to see the choice of MicroShade type in the 2D report by clicking Show advanced details. It is also possible to assign a specific MicroShade type by using the Advanced tab under materials. Simulation settings When simulating with MicroShade in LightStanza, we recommend using the 5-phase method, as this method gives the shortest simulation time. For grid illuminance calculations the simulation parameters should be set to high or very high quality with a minimum of 6 ambient bounces (ab) in order to give accurate results. For annual grid simulations both draft and high quality can be used, since the results does not change significantly between the two, although there is a tendency to have more light the higher quality settings.

3 Setting up a simulation in LightStanza with MicroShade Applying MicroShade to the project 1. LightStanza uses external 3D modelling tools as a basis for the simulations. Models from SketchUp, Rhino and Revit can be used and imported. Before importing the models into LightStanza, be careful to read the Preparing your Model for Generating Results in LightStanza section under the Help tab in the LightStanza app. 2. Windows are recognized in the following way in LightStanza, depending on the 3D modelling tool used: a. SketchUp Windows are recognized as glass material (less than 100% opacity) b. Revit - Windows are recognized as glass material (less than 100% opacity) c. Rhino - While windows are recognized as glass materials in SketchUp and Revit, in Rhino you must assign an opaque blue material to your windows for them to be recognized in LightStanza. When setting the layer color for your windows, change the color of the material to blue, which is RGB (0,0,255). Anything that is set to blue will be uploaded into LightStanza as a window or skylight, so make sure you remove any extra blue materials that you would not like to be uploaded as a window or skylight. 3. LightStanza comes with predefined MicroShade 2-layer and 3-layer glazings. To apply a 2-layer or 3-layer MicroShade glazing to the project, navigate to the Materials tab in the left-hand menu. MicroShade is listed as a Complex Glazing and can be found under Material Library. Figure 1: MicroShade product materials can be found under "Material library" in the "Materials" tab. 4. When the appropriate MicroShade product has been selected, the MicroShade material is added to the glazing by clicking on the glazing surface with the paint bucket. If the window is grouped together with other windows, the MicroShade material will be added to the whole group by default. To change this, click on the paint bucket to remove the G next to it. The MicroShade material can now be added to individual glazing surfaces. a. To check if the MicroShade material has been applied correctly, hover the mouse over the MicroShade layer in the materials tab. The surfaces with MicroShade applied will now be highlighted in the model view. Figure 2: When the appropriate MicroShade material has been chosen, it can be added from the "In Design" tab to the project.

4 5. If MicroShade FILM ONLY is chosen, the model needs a specific window geometry as described below: a. When a window opening has been constructed in your model, create a surface 1 mm from the façade opening. Create a similar surface 1 mm in front of the surface towards the building exterior. The exterior surface will represent the MicroShade and the interior surface will represent the window. Figure 3: Using the "Tape measure tool" in SketchUp. Figure 4: Adding a window surface 1 mm into the facade opening. Figure 5: Creating a MicroShade surface. Figure 6: Placing the MicroShade surface in front of the window surface. 6. If the model has been constructed for a custom glazing build-up, apply a MicroShade FILM ONLY material to the glazing exterior surface and a Glass material to the interior glazing surface.

5 Daylight simulations with MicroShade in LightStanza LightStanza can calculate daylight for both a specific point in time or annually. 1. After MicroShade has been successfully added to the windows, a daylight simulation can be performed from the Activity tab. Simply click on New and set-up your simulation. UDI and sda simulations can be found under the Annual Grid Illuminance. Figure 7: Simulations can be performed from the "Activity" menu. 2. When the simulation has been set-up, start the simulation by pressing Start simulation. Because LightStanza is cloud-based, the browser window can be closed while the simulation is running and opened again when the simulation has finished. Depending on your subscription, several simulations can be calculated at the same time. 3. When simulating with MicroShade in LightStanza, we recommend using the 5-phase method, as this method is the fastest. The simulation parameters should be set to high or very high quality with a minimum of 6 ambient bounces (ab) for grid illuminance calculations. For annual simulations both draft and high can be used. 4. When the simulation is done, click on the activity in the Activity menu and view your result, either directly on the model with 3D view or get a 2D report, by clicking either the 3D or 2D icon below your activity. 5. Currently LightStanza can only calculate sda during occupied hours, however, it is possible to calculate the annual illuminance for all hours of the year and export an output file for post-data processing in order to calculate sda in accordance with the European standard EN Figure 8: Example of a result of a simulation, shown in a 2D report.

6 A rotation of MicroShade is normally done to optimize the g-value. For vertical facades, MicroShade are never rotated, while MicroShade in roof windows can be rotated depending on the orientation and inclination of the roof. Rotation should be considered for orientations between northeast (45 ) and northwest (315 ) for all roof windows. Please contact MicroShade A/S at support@microshade.dk in these cases, to get the right rotation angle. For more information on which MicroShade type to choose for your project, please see the selection guidelines on or contact us at support@microshade.dk. MicroShade A/S Gregersensvej 1F, DK-2630 Taastrup, Denmark VAT No. DK info@microshade.dk The information above is given without liabilities for MicroShade A/S. The right to changes is reserved.