[Bldg-sim] Modelling 90.1 Baseline Envelope for Existing + Additions

[Santiago Velez]

I will do that and then post back when this is settled to share the
experience and  keep building this virtual knowledge base.
Thanks again.



2013/11/5 Nick Caton <ncaton at smithboucher.com>

>  I also agree with Maria’s input.  When existing conditions are known,
> those should supercede the baseline requirements set up for to address new
> construction.
>
>
>
> I’ve experienced a grouping of major renovation LEED projects where the
> reviewer in fact pushed me to document and model actual existing opaque
> envelope constructions instead of the standard baseline constructions,
> which actually boosted the performance ratings quite a bit.  This was
> simple on my part as I already had the needed information worked into my
> proposed model.
>
>
>
> In making your case with your reviewer ahead of time (which I’d reinforce
> as sound advice) and for your model documentation moving forward, I advise
> clearly and separately documenting the area totals for skylights and roof
> areas between the existing/untouched portions of the building and the new
> areas of the building.  As you originally posed the question to the lists,
> we had to speculate in that direction.
>
>
>
> ~Nick
>
>
>
> [image: cid:489575314 at 22072009-0ABB]
>
>
>
> *NICK CATON, P.E.*
>
> SENIOR ENGINEER
>
>
>
> Smith & Boucher Engineers
>
> 25501 west valley parkway, suite 200
>
> olathe, ks 66061
>
> direct 913.344.0036
>
> fax 913.345.0617
>
> www.smithboucher.com
>
>
>
> *From:* santiago at zondae.com [mailto:santiago at zondae.com] *On Behalf Of *Santiago
> Velez
> *Sent:* Tuesday, November 05, 2013 11:27 AM
> *To:* Maria Karpman
> *Cc:* Nick Caton; bldg-sim at lists.onebuilding.org
>
> *Subject:* Re: [Bldg-sim] Modelling 90.1 Baseline Envelope for Existing +
> Additions
>
>
>
> Maria thanks for sharing your opinion. I will reach out to the reviewer.
>  It's good to know there can be different interpretation. I do understand
> that if you are certifying as "New construction and Mayor renovations" it
> might make sense that you need demonstrating savings against the full new
> Baseline defined by Appendix G.  It would be nice if future editions of the
> standard were more clear about this and other issues that seem to fall in
> grey areas.
>
>
>
> Thanks.
>
> Santiago.
>
>
>
> 2013/11/5 Maria Karpman <maria.karpman at karpmanconsulting.net>
>
> Santiago,
>
>
>
> I would reach out to the reviewer and argue that your original
> interpretation is correct. Appendix G Table 3.1.5 f that you quoted below
> clearly suggests that the baseline building design for renovation projects
> shall reflect existing conditions prior to any revisions. The section
> covers all aspects of envelope including thermal and solar properties,
> assembly type, and surface area, so there is no indication that the
> “existing conditions” mentioned in 3.1.5 f exclude fenestration / skylight
> area. I don’t see why this rule should be void for projects that include
> both renovation and addition. Section G1.3 is also relevant: *G1.3
> Trade-Off Limits. *When the proposed modifications apply to less than the
> whole building, *only parameters related to the systems to be modified
> shall be allowed to vary*. Parameters relating to unmodified existing
> conditions or to future building components shall be identical for
> determining both the *baseline building performance *and the *proposed
> building performance*. Since the window/skylight area is not modified, it
> should produce neither penalty nor credit for the proposed design.
>
>
>
> Maria
>
>
>
> *From:* bldg-sim-bounces at lists.onebuilding.org [mailto:
> bldg-sim-bounces at lists.onebuilding.org] *On Behalf Of *Santiago Velez
> *Sent:* Monday, November 04, 2013 7:16 PM
> *To:* Nick Caton
> *Cc:* bldg-sim at lists.onebuilding.org
> *Subject:* Re: [Bldg-sim] Modelling 90.1 Baseline Envelope for Existing +
> Additions
>
>
>
> PS. : My interpretation was mostly based on *Appendix G Table 3.1.5 f)
> "Existing Buildings. For existing building envelopes, the baseline building
> design shall reflect existing conditions prior to any revisions that are
> part of the scope of work being evaluated."*
>
>
>
>
>
>
>
> 2013/11/4 Santiago Velez <santiagogvelez at gmail.com>
>
> Nick, thanks for the response. The answer is yes, I'am trying to make a
> case for exceeding the 5% threshold for existing bit of the project, which
> is not modified.
>
> The project is a big existing conditioned warehouse, with lots of
> skylights (18% of roof area), the new bit is an office building, with more
> skylights (properly shaded this time!). I thought it would be fare to have
> a baseline which maintains the existing bit exactly the same (18%
> skylights), and the new addition according to Table G3.1.5 (5%). The global
> skylight area for the whole project is *12%*, and this was reviewed.
>
> The opposite happens for vertical fenestration, warehouse has almost no
> windows, and the new office is fully glazed. With the same criteria,
> existing stays the same, new is 40% max; then the proposed ends up with
> global 32% WWR and baseline only 28%. This was reviewed as well.  Am
> I explaining my self?
>
>
>
> I thought this would be fair, and in fact it made so much sense I thought
> it was the only possible interpretation... Its very good to remember one an
> be *very* wrong.
>
>
>
> So my approach should be:
>
> - For vertical fenestration, 32% both baseline and proposed.
>
> - For the skylights, I would multiple every skylight by  5/12 to get a
> global 5% skylight.
>
>
>
>  Hmmm....energy savings are going to plummet.
>
> Thank you again Nick.
>
>
>
> Santiago.
>
>
>
> 2013/11/4 Nick Caton <ncaton at smithboucher.com>
>
> Proposed and Baseline areas/layouts matching works perfectly until you
> exceed either 40% for vertical or 5% for skylights.  See Table G3.1.5,
> baseline items c. and d.  This might be coincidence, but just to be cover
> all bases: 28% + 12% = 40% is an incorrect reading – the skylight and
> vertical fenestration thresholds are independent.
>
>
>
> I think you are to leave the vertical fenestrations alone (being under the
> 40% threshold) and you need to proportionally lower the area of the
> skylights in the baseline model to get back to 5%.  Proposed model needs to
> match actual design so it’s skylights remain the same.
>
>
>
> I’m not certain how or if the project being a major renovation has any
> bearing on the matter.
>
>
>
> Are you making the case that the existing skylights are envelope
> components not being touched, and so should remain equal in area between
> the models despite exceeding the 5% threshold?  Do you have additional new
> skylights complicating the matter?
>
>
>
> ~Nick
>
>
>
>
>
> *NICK CATON, P.E.*
>
> SENIOR ENGINEER
>
>
>
> Smith & Boucher Engineers
>
> 25501 west valley parkway, suite 200
>
> olathe, ks 66061
>
> direct 913.344.0036
>
> fax 913.345.0617
>
> www.smithboucher.com
>
>
>
> *From:* bldg-sim-bounces at lists.onebuilding.org [mailto:
> bldg-sim-bounces at lists.onebuilding.org] *On Behalf Of *Santiago Velez
> *Sent:* Monday, November 04, 2013 3:20 PM
> *To:* bldg-sim at lists.onebuilding.org
> *Subject:* [Bldg-sim] Modelling 90.1 Baseline Envelope for Existing +
> Additions
>
>
>  Dear forum users, I have modelled a project following Appendix G. and
> have received a review regarding my interpretation of % glazed area on the
> baseline.
>
> The project is a mayor renovations + Additions (existing conditioned
> warehouse + New office building attached). There were no modification on %
> area of vertical and horizontal glazing on the existing bit of the building.
>
> My approach was to model existing envelope, shape and fenestration,
> exactly the same in both proposed and baseline. The addition was modelled
> following the "maximum 40% for vertical fenestration and 5% for skylight"
> rule. The result of the whole building for baseline is, 28% vertically
> glazed and 12% of skylights (the existing bit was very different than 40%,
> and 5% respectively)
> The reviewer states that the end result for the baseline should still be
> 40% and 5%. It is not very clear to me how would I get there.. Do I have to
> make the existing fenestration proportionally smaller, just like I would do
> for the baseline of a completely new building?
>
> Thanks in advance.
>
> Santiago.
>
>
>
>
>
>
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131105/09097842/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 1459 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20131105/09097842/attachment-0002.jpeg>