[Bldg-sim] Calculating solar reflectance using Ecotect

[Anupam Jain]

Priya,

It is not possible to measure the physical properties of a material through
a software. As Michael said, it needs to be measured through field
instruments. However, you seem to want to compare the effects of absorptance
and reflectance of different facade materials for a given design problem. Is
that correct? If yes, you can definitely simulate the reflectance and
absorptance of a given material using Ecotect. This page gives complete
details on how to do it: http://squ1.org/wiki/Solar_Absorption.

You can define the characteristics for two different materials and apply
them one by one to the facade under investigation to see how it makes a
difference. However, I am not too confident of Ecotect's capabilities in
this regard yet. For example, I modified the external layer of a material
assembly (for a wall) and recalculated physical properties through Ecotect.
The solar absorptance did not get updated. This leads me to believe that the
feature is not reliable. If you are familiar with IES Virtual Environment,
then that is a much better tool for studying the changes in material
assemblies. If you're just interested in the heat gain/loss, thermal lag
kind of stuff, a very simple tool that you can use for free is OPAQUE (
http://www.energy-design-tools.aud.ucla.edu/). This link has other useful
tools that you might already be using (they are so helpful!).

Hope this helps.



Thanks,

Anupam


*---*

* *

*Anupam Jain*, B.Arch, MBS

Graduate Mechanical Engineer, LEED AP



*Buro Happold Consulting Engineers, Inc.*

9601 Jefferson Boulevard, Suite B

Culver City, CA 90232, USA

Tel:         +1.310.945.4824

Fax:         +1.310.558.9697

Email:    anupam.jain at burohappold.com

Web:       www.burohappold.com



This transmission is confidential and intended solely for the person or
organization to whom it is correctly addressed. If you are not the intended
recipient of this transmission, you should not take any action in reliance
on it. Further, this transmission may contain confidential design and other
information owned by Buro Happold Consulting Engineers Inc. You should not
copy, distribute, use, offer for sale or hire such information or in any way
infringe the design and intellectual property rights of Buro Happold
Consulting Engineers Inc. It is intended that communication by email from
Buro Happold Consulting Engineers Inc. or its employees is limited to
communications connected to the services provided by Buro Happold Consulting
Engineers Inc. Buro Happold Consulting Engineers Inc. accepts no liability
for any communications not connected to the services it provides. Computer
viruses may be transmitted or downloaded onto your computer system via email
communication. It is the recipient's responsibility to take any action
necessary to prevent computer viruses being transmitted in this way.
Accordingly, Buro Happold Consulting Engineers Inc. disclaims all
responsibility which arises directly or indirectly from such transmission of
computer viruses.

P* **Save a tree...Please don't print this e-mail unless you really need to*




> Message: 1
> Date: Sun, 13 Dec 2009 18:05:23 +1300
> From: Michael Donn <Michael.Donn at vuw.ac.nz>
> To: Priya Premchandran <priyap at serapdx.com>,
>        "bldg-sim at lists.onebuilding.org"        <
> bldg-sim at lists.onebuilding.org>
> Subject: Re: [Bldg-sim] Calculating solar reflectance using Ecotect
> Message-ID:
>        <
> 00090EAB15B77E48B4DC5B82BD3F4CB56A82940607 at STAWINCOEXMAIL1.staff.vuw.ac.nz
> >
>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Hi
>
> What you describe sounds like an impossibility for all software, and is
> certainly I think impossible for Ecotect. Perhaps I am misunderstanding the
> question? You seem to be asking whether Ecotect (or other software products)
> can measure the physical properties of a building facade? Building physical
> properties are input parameters to simulation programs and to Ecotect. One
> needs a field instrument to do this, not a piece of software..?
>
> m
>
> From: bldg-sim-bounces at lists.onebuilding.org [mailto:
> bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Priya Premchandran
> Sent: Saturday, 12 December 2009 2:33 p.m.
> To: bldg-sim at lists.onebuilding.org
> Subject: [Bldg-sim] Calculating solar reflectance using Ecotect
>
> Hello,
>
> Has anyone used Ecotect to analyze solar absorption/reflectance for a
> surface , for example a building fa?ade? Using Ecotect, it is possible to
> calculate the incident solar radiation values but I am more interested to
> find if the software could be used to  determine the solar
> reflectance/absorption values to help compare various design options.
>
> Any thoughts or suggestions on this issue is very much appreciated.
>
> Thanks,
> Priya
>
> SERA
> architecture    urban design+planning    interior design    serapdx.com<
> http://www.serapdx.com/>
>
> priya premchandran, LEED? AP
> leed? coordinator    priyap at serapdx.com<mailto:priyap at serapdx.com>
> 338 nw 5th avenue, portland, oregon  97209
> d: 503.445.7368    t: 503.445.7372     f: 503.445.7395
> P Please consider the environmental impact before printing this email
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20091213/75d459f3/attachment-0002.htm>