why shadow analysis?

As our cities and towns grow taller and denser, understanding the effects of shading is growing in importance.  Whether required by shadow ordinances or as a response to community concerns, an independent, accurate and detailed shadow analysis is an increasingly essential component in the development, approval--and at times litigation--of larger real estate projects. 

Historically, graphical shadow studies have typically been performed by a project’s architect.  This is appropriate if the project is small and the analysis needs are modest, requiring a few snapshot images taken on a few dates without a lot of detailed shading context.  The drawback of these simple studies is that they leave many critical questions unanswered, such as:

What areas would receive some new shadow at some point throughout the year?

What is the total increase in shadow generated by the project over the course of a day/season/year on a specific feature (park, school, church stained glass window, etc.)?

What specific dates and times would new shadow would be present?

When would the largest shadows be present?  How long would they last?

What would be the maximum building envelope that would not cast any new shadows on a specific feature?


PreVision Design answers these questions and more through our advanced analysis of project shading effects on surrounding properties and specific features.  Using our proprietary software tools and techniques, the precise time, location, duration, and areas of existing vs. new shadow can be calculated and mapped.  To further ensure accurate findings, PreVision Design has industry partners who generate detailed 3D model data for urban areas worldwide.  For work in more remote areas, or when an analysis requires an even higher degree of detail and precision, we perform our own drone-based photogrammetry.


Each study we produce is specifically tailored to the needs of the project or to conform with the necessary regulations.  In San Francisco, the detailed reporting required by local codes requires extensive written reports which include shading calculations, graphics, as well as a written narrative of findings.  Other projects need different or more focused deliverables, such as quantitative data findings, color-coded graphics (static or "heat-map"), qualitative narratives, or dynamic shading animations. 

When possible, we like to partner with design teams in the early stages of the project, where we can provide analysis and input on project massing options and alternatives.  Identifying and avoiding problematic shading impacts in the early going can help sidestep a lot of costly headaches later in the process.

In addition to our technical expertise, the PreVision Design team has a strong foundation background in architecture, real estate development, and planning/zoning, which allows us to understand the broader needs and context of the project as well as effectively communicate with all members of the project team.  We let our software do the heavy-lifting for us, so we’re able to be efficient and turn projects around to meet tight deadlines.

We’d love to hear about your project, so please reach out to us at info@previsiondesign.com.