I cant get a simple zone calculation right

[Anonymous]

I was going to produce material for calculation use and I wanted to test the different parameters... so I made a small hut with a total wall surface (no doors or windows) of 48 m2 and then I added a door of 2 m2. What do I get from AC as wall surface...yeah... 47m2. I thought it would be intuitive to squeeze every little square millimeter from the 3D model 

[Aussie John]

Mathome
you havnt said how you got the area.
It is possible to get the area of either side of the wall which of course are different (in most instances)

[Anonymous]

Aussie wrote:
Mathome
you havnt said how you got the area.
It is possible to get the area of either side of the wall which of course are different (in most instances)

Oki!
Here comes the model. The yellow ring shows the wall surface and it should be (perimiter*wall height-door area-window area). In figures it should be 20*2,4-2-1=45m2 but I get 46,6m2 which makes me really confused!?!?!?
/Mats

[Anonymous]

Mats,

It's hard to say without inspecting the model but I am guessing that your calculation may not be reducing the wall surface by the smaller opening. I forget where it is now, but there is a setting somewhere about for a minimum opening size for reducing the calculation.

That only accounts for one square meter though. Regarding the six tenths of a meter; the only thing I can think of is perhaps the door is somehow being reduced to the actual panel size in the calculation.

[Anonymous]

Thank you!!!

I found it under "set up list schemes". The reduction was set to reduce wall quantities if an opening was larger than 1 m2 (heavens know why). Now I have set the limit to 100m2 just in case...

Mats

Matthew wrote:
Mats,

It's hard to say without inspecting the model but I am guessing that your calculation may not be reducing the wall surface by the smaller opening. I forget where it is now, but there is a setting somewhere about for a minimum opening size for reducing the calculation.

That only accounts for one square meter though. Regarding the six tenths of a meter; the only thing I can think of is perhaps the door is somehow being reduced to the actual panel size in the calculation.

[Djordje]

mathome wrote:
I found it under "set up list schemes". The reduction was set to reduce wall quantities if an opening was larger than 1 m2 (heavens know why).

That is the rule in some places, mine included; I think it originates in DIN. You ignore openings that are less than one square meter of area in the quantities calculation.

[Anonymous]

Djordje wrote:

mathome wrote:
I found it under "set up list schemes". The reduction was set to reduce wall quantities if an opening was larger than 1 m2 (heavens know why).

That is the rule in some places, mine included; I think it originates in DIN. You ignore openings that are less than one square meter of area in the quantities calculation.

I think this has to do with the fact that there is no savings in materials with smaller openings. The scraps are too small to be significant. It's a different matter for heat loss calculations of course.