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ASHRAE Solar Intensity Table Question

jb9 Member Posts: 104

I am doing the Solar Gain portion of my heat calculation and my structure is at 43 North Latitude. I am using the ASHRAE Solar Intensity Data but it only has orientation values for 40 and 48 North Latitude. Do I do some kind of extrapolation between the two values or just use the values for 40?



  • Mark Eatherton
    Mark Eatherton Member Posts: 5,837
    I would suggest you go to Robert Beans web site, and ask him that question. He's one of the most knowledgeable people I know when it comes to ASHRAE related questions.

    My personal thoughts are that you can probably safely extrapolate. The exposure is pretty consistent, except where local climatic conditions can interfere (Lake Snow effects along the Great Lakes for example)

    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • jb9
    jb9 Member Posts: 104
    Thanks Mark. I actually was able to write a formula that would interpolate the values for 43 North Latitude. I will definitely reach out to Robert as well.