Frequently Asked Questions

Who uses LightStanza?
LightStanza is used by Architects, Sustainability and High Performance Design Specialists, Daylight Consultants, Lighting Consultants, LEED Consultants, Energy Modelers, and Project Managers.

What does LightStanza use for its lighting simulation engine?
LightStanza uses the trusted and validated US Department of Energy Radiance Engine, which is a reference for other lighting simulation engines. For annual simulations, LightStanza automates Radiance’s latest fast 5-phase method. The 5-phase method is designed to work with BSDF data, accurate descriptors of daylight products like skylights, blinds, and redirect films for windows. LightStanza’s implementation of the 5-phase method is unique in that its fully automated, saving several hours of setup time per building by expert consultants.

What is Special about LightStanza’s LEED Daylight Credit Report Card Feature?
LightStanza offers a 1-click, comprehensive (Option 1 and Option 2), USGBC approved LEED v4 report card. LightStanza rigorously follows the reference IES LM-83 document to assure that your scores will be accepted by the USGBC so you can rely on the output of LightStanza to guide your daylight design.

LightStanza, unlike any other daylight tool, automatically models blinds which are required for this calculation. Also unique to LightStanza is that you can use your model from Revit, Rhino, SketchUp or ArchiCad as is, without having to simplify or rebuild your model to get it work.

Why would I want to buy a daylight-only program, versus a program that does both daylight and energy?
A program that offers more features compromises its ease of use, accuracy, and capabilities. Energy modeling tools force you to use modeling constraints that are specific to them. For example, Sefaira, IES VE or OpenStudio will force you to simplify, rebuild, your building to run their energy calculations. This simplification of using paper-thin walls, omitting blinds, and removing geometric detail skew both quantitative and qualitative lighting calculations.

If someone offered you a spork it may be convenient, but unlikely as capable or good of an experience as having a spoon and fork. Tools that sell themselves as a complete energy and daylight analysis tools are making compromises.

Typically other programs subvert IES- LM-83 by not modeling blinds (so they will overpredict daylight, not taking into account how people actually use buildings), and/or use paper-thin walls for convenience of producing an energy calculation, as well as employ sub-standard calculation methods such as “real-time” precision. LightStanza offers an honest Spatial Daylight Autonomy

Do I need a plugin to run LightStanza?
LightStanza is web-based and does not require a plugin. Unlike other building performance tools, it requires no special model building or simplifications to get started. There is a plugin available for custom illuminance grids in Revit, but this is not required for generating results.

What is LightStanza’s value for computing unlimited LEED Report Cards if I only want to do a few (e.g. 3) LEED Projects in a year?
Because it’s so easy to run comprehensive LEED v4 calculations in LightStanza, we have customers who have "learned how to do it” by starting to run report cards early in the design process, and by iterating. They have been able to get 3 and even 4 credits (yes, you can get 4)!

We have people come to us at the end of a design process and it’s frequently too late to achieve the credit-- those that iterate early can get daylight right. Developing different types of solar control, adding the right types of skylights and other apertures and, refining material selections are strategies you can test with LightStanza all throughout the design process.

Some people say that LEED does not set the bar high enough for great daylit buildings, so why bother?
Many of the ingredients of high quality daylight are touched upon by LEED-- comprehensive climate-based annual analysis, daylight sufficiency, and protection from glare are part of its Option 1 formula. It will be challenging to find a great solution that does not register in the LEED rubric.

Nevertheless, LightStanza goes beyond LEED in several ways-- false-color renderings, Daylight Glare Probability scores, point-in-time illuminance animations, daylight factor, six different annual daylight metrics, and many more advanced analysis features are available.

So what’s the big deal about having an accurate Spatial Daylight Autonomy Calculator?
Spatial Daylight Autonomy in LEED v4 is defined by the IES LM-83 reference document, which is correlated with empirical studies of what people like in daylit buildings. LightStanza has gone through great lengths to implement this correctly, which is missing from other software.

Why is it important to have renderings in a daylight program?
Because this is what the eye sees and is the best proxy for daylight quality. Programs that just draw graphs are giving you an impoverished representation of light. For example, for measuring glare, just looking at a work plane graph does not tell the full story since they eye is positioned vertically.

Can I run custom settings with LightStanza like I can run Radiance directly?
Yes, LightStanza allows every Radiance parameter to be completely customized for renderings and grid calculations.

What are the benefits of LightStanza being a web application over the PC program DIVA for Rhino? Both strive for accuracy, so why not just save on initial costs and purchase less functional PC software?
Calculation Speed: Running LightStanza analysis is like having multiple workstations on your desk as well as having a skilled technician figuring out every second how to distribute each calculation efficiently across machines. In addition, requests can be run in parallel with LightStanza. Hence, as part of your subscription to LightStanza, you are buying hardware and machine-level supervision on demand.

Organizing results: LightStanza keeps a filterable graphical history as well as simulation details for every analysis that is run. Compare this to DIVA or other PC tools that write raw data files without simulation inputs to your hard disk that are nearly impossible to retrieve and decipher as soon as the next day.

Maintenance: LightStanza does not require the user to install any software, always being up-to-date. PC software requires lengthy installations, constant updates for consistency within the organization, network licenses, and the need to directly edit files on their hard disks to operate.

Ease of learning and use: As a web-based application with countless R&D hours on user-experience, LightStanza does not require users to learn and debug the “expert only” Radiance syntax as well as complex scripts to get to high-quality analysis. This eliminates months of training as well as provides for a more reliable workflow. We are often told the speed-up in using LightStanza is not just the cloud compute, but the efficiencies in workflow.

Flexibility: LightStanza uses the Autodesk Forge conversion service so that you can work with models in a variety of formats (Revit, Rhino, SketchUp, IFC), not just Rhino. If your office uses Revit, you can directly import .rvt files into LightStanza. With DIVA for Rhino, you have to convert your drawings to DWG/DXF which homogenized all your model materials. Thus, you will need to spend 10-12 hours reassigning your glass to be glass as well as changing all the surface reflectances before starting any analysis.

Is my information secure when I use LightStanza?
Yes. Here is how LightStanza keeps your information safe:

1. Credit Card Information is securely stored with © Stripe. No credit card information is stored locally. To learn about Stripe security, please visit

2. All files are isolated from the public. Designs, result images, and result data if downloads are “opted in” are stored through Google Cloud. For information about Google Cloud security, please visit

  • All sensitive routes of communication in the app are controlled using Access Control Lists (ACL), implemented with standard open source packages and user/team level roles.
  • Permissions are checked again in route-level middleware to limit access to specific database resources - e.g. users must be logged in and can only view designs that belong to their team
  • An enterprise-level application deployment service further protects sensitive data by providing:
    • Authentication (to identify who a user is)
      • No anonymous authorization allowed
      • OpenId Connect Tokens to authenticate users
      • No insecure ports utilized
    • Authorization (to determine what a user is allowed to do)
      • For in-app authorization, see above (ACLs)
      • For other access (e.g. file service and database), LS uses role-based authorization controls. Only LS employees have roles that allow direct access to anything other than the app.
    • Admission Control (to allow a person to modify/change components of the app)
      • Restricted access to all components (e.g. app, database)
      • LS always pulls new software images from a private repository, so credentials are always needed to make changes to the code in any component.

3. Communications between users and the app are encrypted using SSL, with a new encryption certificate renewed each year.

4. When the LightStanza Application is accessed, these steps are taken to prevent users from seeing one another’s data: