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Difference between adiabatic surface and high R value

Hi,

I am trying to minimize conductive heat transfer through the envelope.

I can do this by setting the surface to adiabatic through the measure Set Exterior Walls and Floors to Adiabatic....

Figure 1: Adiabatic Measure with conduction still occuring from ground into building. adiabatic measure

Or, for envelope members that are not the ground (roof and walls), I can increase the R-value to a very high percentage to approximate adiabatic, using the following measure.

Figure 2: R Value Increase Measure with Large (>>100%) Increase.

r value measure r value measure 2

Making a surface adiabatic removes windows and stops ALL heat transfer through that surface.

If I still want fenestration in my walls and solar, radiative, and convective gains on my walls and roofs, can I still use the adiabatic surface measure? I am assuming no, but would like to confirm.

If I cannot set the walls and roofs to adiabatic, what is the max % increase I can input into the above measures without the simulation breaking? @David Goldwasser?

Difference between adiabatic surface and high R value

Hi,

I am trying to minimize conductive heat transfer through the envelope.

I can do this by setting the surface to adiabatic through the measure Set Exterior Walls and Floors to Adiabatic....

Figure 1: Adiabatic Measure with conduction still occuring from ground into building. adiabatic measure

Or, for envelope members that are not the ground (roof and walls), I can increase the R-value to a very high percentage to approximate adiabatic, using the following measure.

Figure 2: R Value Increase Measure with Large (>>100%) Increase.

r value measure r value measure 2

Making a surface adiabatic removes windows and stops ALL heat transfer through that surface.

If I still want fenestration in my walls and solar, radiative, and convective gains on my walls and roofs, can I still use the adiabatic surface measure? I am assuming no, but would like to confirm.

If I cannot set the walls and roofs to adiabatic, what is the max % increase I can input into the above measures without the simulation breaking? @David Goldwasser?

Difference between adiabatic surface and high R value

Hi,

I am trying to minimize conductive heat transfer through the envelope.

I can do this by setting the surface to adiabatic through the measure Set Exterior Walls and Floors to Adiabatic....

Figure 1: Adiabatic Measure with conduction still occuring from ground into building. adiabatic measure

Or, for envelope members that are not the ground (roof and walls), I can increase the R-value to a very high percentage to approximate adiabatic, using the following measure.

Figure 2: R Value Increase Measure with Large (>>100%) Increase.

r value measure r value measure 2

Making a surface adiabatic removes windows and stops ALL heat transfer through that surface.

If I still want fenestration in my walls and solar, radiative, and convective gains on my walls and roofs, can I still use the adiabatic surface measure? I am assuming no, but would like to confirm.

If I cannot set the walls and roofs to adiabatic, what is the max % increase I can input into the above measures without the simulation breaking? @David Goldwasser?