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Heat Loss calculation anomalies

Robert_H Member Posts: 140
I have two situations that are not clear to me in the heat loss calculation.  This project is cast iron radiators with mod/con system.

1.    When two rooms have a large opening between then them, in this case a half wall running the length of the two spaces. One space is a room 174sqft the other a hall of 89 sqft.  Do you treat them as if there is a solid boundary for the calculations and determining radiation for each space?

2.     In the same case if I can’t fit the required radiation in one of the spaces (the hall) can I just calculate the combined heat loss and ensure that the combined radiation meets the combined heat loss.

3.    Upstairs/Downstairs: downstairs hallway (89 sqft), with stairs leading to upstairs hall (52sqft).  At the top of the stairs the upstairs hall runs to the left as in an L shape. The stairwell space on the second floor is about 30 sqft.  Is the stairwell area on the second floor considered part of the first floor hallway for radiance?

I hope this not to confusing. Hopefully the sketches will clarify everything.




  • Robert_H
    Robert_H Member Posts: 140

    showing hall and Room with half wall between them
  • Robert_H
    Robert_H Member Posts: 140

    pictures are not uploading. Ill sort it out...
  • Robert_H
    Robert_H Member Posts: 140
    Trying downstairs

  • Robert_H
    Robert_H Member Posts: 140
    Upstairs Hall

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,506
    My thoughts

    What software are you using? The reason I ask is because they do things different ways.

    1. I would treat the first floor as 2 rooms. Remember in those spaces, the half wall calc in both rooms would show as interior walls.

    2. I think you'll get plenty of radiation on the half wall. (89 sq ft). How bout a nice properly sized powder coated radiator?

    3. I would just count the second floor hall not the steps. It won't make any difference.
  • Robert_H
    Robert_H Member Posts: 140
    Thanks Steve!

    I'm primarily using the spreadsheet created by Andrew Ensminger(Crown).  not a lot of bells and wistles but nothing is hidden from the user.

    I’ve tried several programs to run the heat loss Uponor’s and Taco’s FloPro. Flopro is nice because you can draw the floor but it has options like "include floor in load" that don't effect calculations but seem like they should. I think they are still working the bugs out.

    your suggestions make sense. I will treat the rooms separately and not worry about the stair area.

    I will be using cast iron radiator in the hall near the entry door. It will be sized appropriately but not powder coated I don't have those toys, yet ;)
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