[Bldg-sim] Above Grade External Wall Area Weighted U-value Calculation

Joe Huang yjhuang at whiteboxtechnologies.com
Sun Sep 29 13:02:27 PDT 2013


What the reviewer said is technically correct, but not often done in 
simple UA calculations because of the difficulty is calculating U-values 
for such thermal bridging.
The effects can be substantial, especially for heavy-mass concrete 
construction. I've seen in China there's a standard method to account 
for thermal bridging in calculating wall U-values. Have not seen a 
similar technique for the US, don't know about the situation in Europe.

Joe

On 9/29/2013 9:31 AM, Sherif Farag wrote:
>
> Dear All,
>
> I have submitted a project for review and received a comment 
> requesting me to include the concrete slabs between floors (Not drop 
> beams) in the External Wall' area weighted U-value calculation, the 
> reviewer believes that concrete slabs acts as a thermal bridge and 
> should be insulated from the outer side (The slab thickness), my 
> understanding that concrete slab shouldn't be regarded as a part of 
> the occupied area and therefore shouldn't be included in the area 
> weighted U-value calculation.
>
> I would appreciate if you can advise on the above query!
>
> Thanks & Best Regards,
>
> *Sherif Farag*
>
> *Senior Sustainability Consultant*
>
> P.O. Box: 127842
>
> Abu Dhabi, UAE
>
> M: +971 55 199 0022 | E: sherif.sabr at gmail.com 
> <mailto:sherif.sabr at gmail.com> | Skype ID: sherif.farag9
>
>
>
> _______________________________________________
> Bldg-sim mailing list
> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
> To unsubscribe from this mailing list send  a blank message to BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20130929/4817cb0b/attachment-0001.htm>


More information about the Bldg-sim mailing list