SBEM Calculations - Incorrect U-Values

[PCully]

Hi,

There was an issue a while back in version 5.8 of <VE> where VE-SBEM would treat surfaces as Personnel Doors when a hole connected two rooms that did not cover all of the internal partition between the rooms, the leftover internal adjacency would be treated as Personnel Doors in the U-value checks. This was an error that BRE corrected some time ago so if you are using <VE> 5.9 or 6 then this should not be an issue.

Can you confirm if this scenario may apply and what version of <VE> you are using please?

Also, just use the CDB to double check the Constructions you think are in use are in use for all doors.

If you still don't find a solution then I will contact you to get the model and check for myself, everything looks ok in the simple tests I have performed so far.

Phil

[PCully]

Thanks for checking this, songs like it may be the same issue.

I have sent you a private email to get the project from you so I can check this out myself.

Before the issue was corrected in SBEM the guidance we issued was to avoid connecting the zones that were causing this issue by holes or to edit the holes so that the issue is avoided - probably not so convenient in many cases but might allow you to keep working with minimum impact on results while I review this.

Phil

[PCully]

Thanks I have the project now so will be able to have a look and confirm it is the same issue.

I'm fairly certain this problem won't occur for new projects built in <VE> 6. The Support dept here haven't had this issue reported since around version 5.8 which suggests to me it is no longer an issue for new projects.

Phil

[PCully]

Just an update on this as it was resolved in the email my colleague David sent to Gary a couple of days ago.

This model contained external holes (in balcony zones in this case) which should never be used in SBEM or Apache DSM simulation. In this scenario SBEM doesn't know what U-value to assign and so the U-value checks get corrupted.

Solution is to always model external holes as glazing.

If you're running DSM using Apache you can always set up MacroFlo opening types for these holes so that the windows are open and then the effects of the air coming into the room are included in results.

Hope this helps any other users who may run into this issue in future

Phil