Lighting Power Density using ElumTools

Since day one of ElumTools, Revit has coexisted and offered several powerful tools for electrical analysis, including Lighting Power Density reporting functionality.  The latest releases of ElumTools include new functionality to make it easier to leverage Revit’s LPD tools as a natural part of the typical ElumTools workflow.

The Create Schedule command now includes some additional parameters which are associated with Rooms and Spaces.  To take advantage of the new electrical parameters, the first step is to create and configure Spaces in the host model.

Once you have Spaces set up, you need to make some decisions about how you wish to use each parameter.  Here is an overview of the role played by each.

Specified Lighting Load

These are intended to be reporting parameters and are fairly easy to define.  At a high level, the Specified Lighting Load parameters are values that are simply entered by the user as a design goal.  They are in no way connected to the Lighting Fixture families which are actually placed in the model.

Specified Loads are defined in the Electrical Instance Parameters of each Space.  See below.  Space Lighting Loads can either be specified “By Space Type”, particularly handy for code compliance evaluation, or individually on a per Space basis.

Actual Lighting Load

Actual Lighting Load is intelligently determined by Revit, based on the Luminaire family instances actually placed in the model.  This is intended to help ensure final design proposals meet the design specification and applicable electrical codes.

For Actual Lighting Loads to calculate as expected, all luminaire families must have a properly configured Electrical Connector.  This is a somewhat complex area and will be the subject of a future blog post. Conveniently, however, all of the families in the Built-in ElumTools library have the Electrical Connector set up “out of the box”, as of version 2018.4.

The luminaire families ship with a default load of 0VA, since each family could potentially represent many kinds of fixtures (with very different loads).  To get accurate LPD numbers, the user simply needs to define the Apparent Load Type Parameter appropriately for each fixture Type.


For Revit to compute the Actual Lighting Loads, the appropriate checkbox must be checked in the Electrical Settings. Otherwise, all Actual Lighting Loads will be reported as zero.

Computation of Lighting Loads can sometimes be a performance intensive process.  Therefore, it can be convenient to disable the load calculation functionality when working with larger models and/or on slower systems.



Luminaire Family Validation Made Easy

When a calculation is invoked, ElumTools automatically checks all Lighting Fixture families in the environment to determine whether the family has valid photometry applied.  If the program detects luminaires without photometry it throws a handy warning, alerting the user of the problem.  This is especially helpful for newbies as a quick check to see whether or not all the families are in order.

However, sometimes this warning will be triggered at times when the user actually intentionally doesn’t have a  photometric file assigned.  Take the case below.

In this case, ElumTools is warning the user that it found 4 table lamps (60 W Incandescent) without valid photometry assigned.  For most serious illumination engineering projects, this is what you want (a table lamp typically won’t be an integral part of a commercial lighting solution).  Often these kinds of families will be included in the Revit project for Rendering purposes, but are not germane to quantitative lighting analysis.

What to do?  You could of course click the “Do not show me this again” check box.  But that is a global change that will prevent the warning from popping in all cases, not just this particular one.

The latest releases of ElumTools now allow the user to “approve” individual Luminaire Types directly in Luminaire Manager.  This lets you suppress the invalid luminaire warning on a case-by-case basis.

By default, ElumTools will throw a warning for all Luminaire Types which show a “Red X” in Luminaire Manager (the way it has always worked).

Now, Luminaire Manager also gives the opportunity to click the “red X” and change it to a more friendly “green X”.  Family Types with green X’s still do not contain valid photometry.  But ElumTools will interpret them as “approved” and will not show a warning.

Similarly, you can also approve Luminaire Family Types which DO have valid photometry assigned.  This has no effect on the behavior of ElumTools (apart from changing the icon in Luminaire Manager) and is simply convenient for documentation.  It is in no way a requirement to approve Luminaire Types prior to calculating.

Behind the scenes, ElumTools stores whether a Family Type has been approved, as a shared parameter called “ElumTools Validated”.  This can be easily scheduled which can serve as a quick way to see which families still need validation (particularly useful on large projects).  Revit even provides some conditional formatting tools to pretty things up.  What fun.

What’s new in 2018.3 (2017.6 and 2016.10 too)

The latest generation of ElumTools is packed with new features, mostly geared to exterior lighting analysis, with some interior applications as well.  The most powerful new feature is the ability to visualize lighting results using isolines and spatial maps.  The video below gives an overview of the feature, along with some tips and tricks.

This release also includes a set of pole mounted luminaire families for use in exterior projects.  Each family can be easily configured to model most common arrangements and the photometry can easily be swapped.  These families solve many of the difficult problems related to nesting the light source as well as building families with multiple sources.

Luminaire Manager also got a face lift, designed to make families with nested light sources easier to work with.  Now you can duplicate, rename, and delete Family Types right in the dialog, reducing the need to go back and forth between Revit and Luminaire Manager.  This can be a big time saver.

Revit 2017 and 2018 users will also be happy to learn that the latest update removes the nuisance “Unsigned Addin Warning” which required users to trust ElumTools at the beginning of each Revit session.  This was accomplished by adding a digital signature to the ElumTools installer and program files, which has the added benefit of improving security and reducing vulnerabilities.

A complete list of changes can be found in the latest Release Notes.

New Commands Available in 2017.3, 2016.7, 2015.10!

The latest ElumTools update includes dramatic new capabilities to use 3D views to sort the portions of the model you wish to compute. You can now compute the Active view, or compute any number of separate 3D views using the Calculate Multiple Views command. These commands allow easy and intuitive control over which elements are calculated. This is particularly handy for phased projects and projects employing multiple Design Options.


The Calculate Views functionality paves the way for another new command, Create Daylighting Views which will allow you to stratify your model into interior and exterior geometry thereby solving the old problem of exterior geometry in daylight calculations.  Now exterior shading devices and adjacent structures can be considered with ease for Daylight Analysis.


In addition to the new calculation functionality, the latest ElumTools update contains many other Enhancements and Bug Fixes, improving both usability and performance of existing ElumTools features.