January 19, 2017

Energy Analysis Modeling (EAM) – Masses


This post is part-one of a four-part series on Energy Analysis Modeling.

Suppose you have two alternate building design options, both created using masses, and you want to evaluate and compare the energy performance of your designs. Well, I have good news for you; you can create two energy analysis models (EAM) studies in about 5 minutes.

The goal here is to establish an energy efficient direction for the design at a conceptual stage. We will go in depth with Revit building elements and things like the thermal properties of materials later in this four-part series. To start, I want to focus exclusively on managing thermal conceptual values applied to various mass surfaces and generalized energy loading according to building type.

All classroom activities on the ground level
Classroom activities stacked

Using masses for your energy analysis model will ask you to select values from a compact dialog that assigns design assumptions. These can be values related to:

• Energy loads such as occupancy (i.e., office, school, or residential)
• Geographic location and a local weather file
• Percentage of glazing on surfaces
• Thermal conductivity of the masses faces (i.e., Walls, Floors, Glazing, and Roofs)

This process will enable you to compare the energy performance of both of your designs and select the one that works best for you.

Once you have decided on the best design option, you can refine the masses by adjusting values per surface or by assigning occupancy per mass zone - I will explore this workflow later in the series. For now, watch my video, Mass Models: Two Energy Analysis Model (EAM) Studies, and let’s see which building design option makes most sense, purely from the energy use point of view.

Don't forget to stay tuned for parts two through four of this series, where I will be covering Mass Overrides for Surfaces and Zones, Building Elements with Masses, and Building Elements and Material Thermal Properties.

For more information on the software solutions, training, and consulting Ideate provides, please visit the Ideate Inc. website.


AEC Senior Application Specialist
Jim Cowan’s extensive AEC design industry experience, Autodesk design solutions expertise, and status as an Autodesk Certified Instructor have made him a sought after university curriculum developer, instructor, and presenter. Jim’s areas of expertise include eLearning, interoperability between solutions, and overcoming barriers to the adoption of Building Information Modeling (BIM). Educated in Architecture at Edinburgh College of Art/Heriot–Watt University and in Landscape Architecture at the University of Manitoba, Jim has special focus on sustainability issues: daylight analysis, sun studies, lighting analysis, modeling buildings, and conceptual energy modeling (models with shading devices). You can learn more from Jim on his YouTube Channel.