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Internal Mass - Surface Area

asked 2020-01-14 16:29:22 -0500

Rezvan gravatar image

updated 2020-01-15 10:02:59 -0500

Hi, I am using e+ to model building energy use. One of the input parameters of "Internal Mass" is surface area. Since my research is at urban scale, I am dealing with hundreds of buildings so calculating the surface area of internal mass for each zone is very difficult. Does anyone know a simplified procedure to estimate surface area of the internal mass (floor wall, etc.)? Can e+ autocalculate surface area of walls, windows, and floors? I really appreciate your help.

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answered 2020-01-14 22:17:44 -0500

I would recommend going to the input/output reference and look at the description of each input field. If you are referring to the object InternalMass it is normally used to describe objects inside a Zone and not the thermal mass in the constructions. You can imagine it being used to account for the internal mass of furniture or other objects inside the zone. I don't know what you mean exactly by "an urban scale", but there is some good information on other answers provided by the developers on why or why not to include multiple buildings in a single simulation.

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Thank you Luis for your answer. I am referring to the "Internal Mass" under "Thermal Zones and Surfaces". I was looking at DOE commercial building reference models and it looks like they calculated the surface area of each zone (excluding window area) and consider that area as some type of wood!! That was confusing because when read the IO reference document, it referred to "Internal Mass" as furniture etc. So, what I understand is that "Internal Mass" is different from building envelope construction, am I right?

Rezvan gravatar imageRezvan ( 2020-01-15 08:09:51 -0500 )edit

You are correct, all the thermal mass associated with construction assemblies gets defined in the Construction objects.

Luis Lara gravatar imageLuis Lara ( 2020-01-15 12:57:57 -0500 )edit

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Asked: 2020-01-14 16:29:22 -0500

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Last updated: Jan 14