Active Member
Posts: 7
Registered: ‎10-20-2009
Message 1 of 12 (2,829 Views)

Ecotect - Thermal values

2829 Views, 11 Replies
10-20-2009 04:28 AM

I am studying civil engineer and are use one semester to evaluate Ecotect and it results.
I am having problems with the thermal calculations in Ecotect, because the calculated temperature inside the zones becomes too small. If I make a small room with almost 100% window it the sought facade the temperature does not raise to most more than 26 degrees (compared to other calculations the temperature should be around 35-40 degrees)
I have tried to change the Solar Heat Gain Coeff. and other parameters for the window and the wall but still the result is not correct

Anybody that has had the same kind of problem or knows that the problems are? Hope that I can get some help.

New Member
Posts: 2
Registered: ‎08-12-2009
Message 2 of 12 (2,829 Views)

Re: Ecotect - Thermal values

11-02-2009 07:47 AM in reply to: nielsthuesen

i encountered the very same problem. i had a simulation model set up
with thermal problematic zones (small room, around 12m², facing south,
almost 100% glazing, location kabul afghanistan, no ac) and was stunned because
the temps never exceeded 29°C. seems there's no need for any optimization.

so, to evaluate i created kind of a bungalow, around 16m² total, low mass,
no insulation, huge windows. a worst case scenario for thermal performance.
simulated in several different summerhot locations. got the same results,
operating temps hovering around 1-2 over outside temp, hardly ever exceeding
the comfort zone.

i really wonder how reliable ecotect output is.

when simulating the same scenario in energyplus, the results look much
more believable. temps easily climb up to 35-40°C, just as i expected they

hope we get any answers from the autodesk staff...

Active Member
Posts: 6
Registered: ‎07-28-2010
Message 3 of 12 (2,814 Views)

Re: Ecotect - Thermal values

07-28-2010 06:50 PM in reply to: fakeson

Hi there,


Did you get a confirmation on the validity of the thermal analysis?


I am having the same problem and begining to doubt the result coming from the thermal analysis within Ecotect. I have modeled a 35m2 6m high building with no ventilation and infiltration from wind. I have applied double glazed windows to roof and the walls so it's pretty much like a green house. I would have expected the temperature inside be higher than the outside on the brightest or hottest day which is not the case shown in Ecotect. The result showed that the temperature inside follows the outside temperature and was below it most of the time.


Can someone comment on the validity of the thermal analysis in Ecotect? Thanks!

New Member
Posts: 1
Registered: ‎10-15-2010
Message 4 of 12 (2,568 Views)

Re: Ecotect - Thermal values

10-15-2010 06:40 AM in reply to: nielsthuesen

seam that like everyone before I'm getting the same problem.
some one of you found out what the solution is?


Active Member
Posts: 6
Registered: ‎07-28-2010
Message 5 of 12 (2,531 Views)

Re: Ecotect - Thermal values

10-19-2010 12:45 PM in reply to: maxschimke

Yea, is there anyone out there who can answer our problem? Thanks!

Posts: 25
Registered: ‎08-31-2010
Message 6 of 12 (2,273 Views)

Re: Ecotect - Thermal values

12-27-2010 01:40 PM in reply to: nielsthuesen

The Ecotect Thermal simulation is not applicable for all situations, and I have found it particulalry untrustworthy in solar heating scenarios.  It might be worth your while you work through the Ecotect export to energy plus, taking advantage of the model you already have.


New Member
Posts: 1
Registered: ‎01-16-2012
Message 7 of 12 (1,824 Views)

Re: Ecotect - Thermal values

01-16-2012 12:55 PM in reply to: nielsthuesen
I am having similar problems... Temperature inside a sun space is lower than exterior temperature during most of tha day.... It is higher onlyduring noon times. After 16:00 it drops very fast, sometimes 10 degrees lower than exterior. . Could anyone help about this, urgent please....
New Member
Posts: 1
Registered: ‎04-04-2012
Message 8 of 12 (1,719 Views)

Re: Ecotect - Thermal values

04-04-2012 12:23 PM in reply to: nielsthuesen



have had similar issues can someone please advice?

Posts: 3
Registered: ‎01-30-2011
Message 9 of 12 (1,623 Views)

Re: Ecotect - Thermal values

05-22-2012 05:24 PM in reply to: nielsthuesen

Have you made sure that the surface normals (for walls, windows, etc...) are facing the right direction (i.e. away from the zone)? This will make a big difference in thermal analysis results.


To view the surface normals, select  Display >> Surface normals. Arrows should appear on the surfaces. If they are pointing towards the inside of the zone, select the surface then click Ctrl+R to toggle the arrow direction. 


Valued Contributor
Posts: 94
Registered: ‎08-31-2010
Message 10 of 12 (1,604 Views)

Re: Ecotect - Thermal values

05-27-2012 12:27 PM in reply to: nielsthuesen

The thermal calculation is Ecotect theoretical premise of the admittance. Is a simplification of analysis, widely used but that "simple". With the data comentais seems that perhaps the data "zone property/Thermal properties" are incorrect.


Are there active systems?

Hope this helps
Best regards

Jose M Carralero.
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