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Does anyone know how to create a ruby script measure for adding metric u values to each construction type in openstudio?

asked 2018-01-21 11:40:38 -0500

David H's avatar

updated 2018-01-22 13:41:05 -0500

How do you add a measure to openstudio for adding metric u-values for construction types automatically. It would be really helpful to have a U value calculator built into the open studio application. Any thoughts?

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@David H Could you try to elaborate on what exactly you need. Do you want to assign same U-value to all constructions? What do you need to automate. I am confused since U-values are assigned to materials not to constructions.

Avi's avatar Avi  ( 2018-01-21 12:51:58 -0500 )edit

For example, when you create a new wall in openstudio, you add layers of materials. Each material has a thermal conductivity value with a specified thickness. The overall construction of the wall then defines the U-value (thermal transmittance). I know very little about writing scripts. So, I was wondering whether it would be possible for a script to be added to openstudio. This script would add indicative U-value for each construction element (walls, roofs). It would be helpful, if you could select whether you require this in IP or SI valves.

David H's avatar David H  ( 2018-01-22 04:52:25 -0500 )edit

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answered 2018-01-21 16:05:41 -0500

There are two measures that set the R-value of a construction to a target value on BCL, one for roofs and one for walls. This changes the thickness of the material layer with the most thermal resistance. It takes IP R value argument, but you could manually convert an SI U value instead, or could alter a copy of the measure to take an argument in your preferred units.

This will Replace Exterior Window Construction used in the model with another window construction already in the model, so this is unitless, but you need to pre-configure the constructions you want to use.

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If you could provide a ruby script to add indicative U-values (thermal transmittance valves) to all walls and roofs in OpenStudio in either SI or IP units, that would be really helpful. I state indicative, as the U-values are dependent on exposure. In principle, if every time you create a new wall or roof in Openstudio, it would provide you with an indicative U-value. If it could also run through every roof and wall in Openstudio and calculate U-values. I appreciate that I can create a new construction set and name the wall with an indicate U-value, but this is very time consuming.

David H's avatar David H  ( 2018-01-22 05:05:57 -0500 )edit

answered 2018-01-23 10:19:33 -0500

updated 2018-01-26 14:02:40 -0500

OpenStudio si an awesome work, but managing the constructions and materials is one of the weakest points. It would be nice if It could be improved with:

  • Grouping materials into families
  • The possibility of altering the position of the materials in a construction
  • Displaying the thermal ressitance of the constructions (while you are making the layers composition).
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Fully agree with you. It would be good to have an indication of thermal transmittance while you create a new construction.

David H's avatar David H  ( 2018-01-29 03:54:20 -0500 )edit

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Asked: 2018-01-21 11:40:38 -0500

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Last updated: Jan 26 '18