[esp-r] Re: clarification of ESP_r air gap specification in low-e glazing

[Jon Hand]

It seems that the ESP-r Cookbook is rather terse on this aspect of
constructions and glazing.  I attach some images which clarify
what is going on.

a) in the materials databases there are a number of classes of materials
    and there is a class labeled GAPS

b) looking in GAPS there are a number of items.  Although there are some
    that are labeled argon filled the best material to pick is the top one
    labeled air gap.

c) the last image is of a tripple glazed window where the standard
    air gap material (equivalent to the legacy material zero) has had
    its air gap resistance revised so that the U value matches the
    manufacturers specification for low-e coatings.

So, leave the GAP materials c/d/e/f/g (in the image) alone for now and select
the GAP material a and modify its resistance once it is in the multi-layer
construction.

The Cookbook should be updated to clarify air gaps.  Thanks for pointing
out the current lack of documentation.

Regards, Jon Hand
________________________________________
From: esp-r-bounces at lists.strath.ac.uk [esp-r-bounces at lists.strath.ac.uk] On Behalf Of Achim Geissler [achim.geissler at intergga.ch]
Sent: 15 June 2011 18:21
To: A.Sdei at brighton.ac.uk
Cc: esp-r at lists.strath.ac.uk
Subject: [esp-r] Re: low with argon fill

Dear Arianna

where did you take the U-value you give from? If you see a reduction in heating load, the U-value used seems to be O.K. If you are using standard TMCs, "low e" or "argon" is only a name and does not have any real influence on the U-value. This is set by the resistance of the gap(s) between the panes of an IGU.

In the construction data base, you can see the U-value when you edit the construction, e.g. change the resistance of the gap. Also, you could check via QA report.

Best
Achim



On Jun 15, 2011, at 4:07 PM, A.Sdei at brighton.ac.uk<mailto:A.Sdei at brighton.ac.uk> wrote:

Dear All,

I am modelling some low-e + argon gas filled windows with esp-r. I change the database settings from ordinary double glazing to low-e + argon gas filled. The U-value increases from 2.8 to over 5. The results are fine (I can see a reduction of heating load) and I am curious to know what is going on there and if I can change the U-value. Does anyone know? Thank you,

Regards,
Arianna

___________________________________________________________
This email has been scanned by MessageLabs' Email Security
System on behalf of the University of Brighton.
For more information see http://www.brighton.ac.uk/is/spam/
___________________________________________________________
_______________________________________________
esp-r mailing list
esp-r at lists.strath.ac.uk<mailto:esp-r at lists.strath.ac.uk>
http://lists.strath.ac.uk/mailman/listinfo/esp-r

achim.geissler at intergga.ch<mailto:achim.geissler at intergga.ch>




-------------- next part --------------
A non-text attachment was scrubbed...
Name: materials_classes.tiff
Type: image/tiff
Size: 20526 bytes
Desc: materials_classes.tiff
Url : http://lists.strath.ac.uk/archives/esp-r/attachments/20110615/b9dd8cde/attachment-0003.tiff 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: gap_materials.tiff
Type: image/tiff
Size: 27980 bytes
Desc: gap_materials.tiff
Url : http://lists.strath.ac.uk/archives/esp-r/attachments/20110615/b9dd8cde/attachment-0004.tiff 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: tripple_glz_layers.tiff
Type: image/tiff
Size: 17554 bytes
Desc: tripple_glz_layers.tiff
Url : http://lists.strath.ac.uk/archives/esp-r/attachments/20110615/b9dd8cde/attachment-0005.tiff