Exterior Surfaces Temperature

[bashar]

Hi. I'm testing some exterior cladding systems and their SRI's. I wanted to know if it's possible to calculate the exterior temperature of different surfaces based on the SRI they have.

Thanks.

[PCully]

Hi,

There are input son CDB for an opaque Construction that allow you to specify Emissivity and Solar Absorptance (or 1 - Reflectance). In this way you can represent the SRI.

I'm not sure how this then relates to the surface temperatures but possibly there are some tests you could run based on these inputs to see if it looks realistic for what you want to measure. (in Vista select any room and go down to surface level and you will see one of the Surface Variables reported is Surface Temperature)

Phil

[bashar]

Thanks Phil, hopefully that'll do it.

[bashar]

Unfortunately it didn't do all of it. I'm trying to find a way where I can compute the temperature of the exterior finish face of the wall, i.e the face that receives direct sunlight.

It might not be possible since, as far as I know, IES only takes into account the room bounded by those walls, and thus only the interior parts that these walls enclose.

I hope there's a way around it.

[PCully]

sorry I don't think it's possible to get the exterior surface temps from Vista. I don't know any way you'd be able to calculate these yourself either.

Phil

[ZapBran]

You can't get external temps - all you have is internal temps and the temp from the weather file.