[Bldg-sim] 90.1-2013 vs 2015 IECC Performance Path Compliance

Mon May 2 10:48:07 PDT 2016

I think the reason for the 15% is that the IECC performance path has not kept pace with improvements to the prescriptive requirement in the rest of the IECC for several cycles. Things like insulation requirements, light power allowance, and HVAC equipment efficiency get updated automatically when the tables the performance path reference get updated. However, there are lots of other prescriptive requirements that have been added to the IECC that have not been captured by the performance path. A few that come to mind include:

1.       30% window to wall ratio limit C402.4.1

2.       Variable speed fans on single zone systems C403.4.1.1

3.       Skylights and daylighting controls for large high bay spaces

4.       Heat recovery required for large service water heating systems C403.4.5

5.       Boiler turndown requirements C403.4.2.5

6.       Additional efficiency options C406

7.       High input service water heating efficiency C404.2.1
I don’t really think it has anything to do with keeping up with ASHRAE 90.1.
__________________________

Michael Rosenberg, CEM, LEED AP
Senior Research Scientist
ENERGY & ENVIRONMENT DIRECTORATE

Pacific Northwest National Laboratory
2032 Todd Street
Eugene, OR 97405
(509) 375-1995
michael.rosenberg at pnnl.gov<mailto:michael.rosenberg at pnl.gov>
www.pnnl.gov<http://www.pnl.gov/>

From: Bldg-sim [mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Elizabeth Gillmor via Bldg-sim
Sent: Monday, May 02, 2016 10:38 AM
To: Duggin, Cory
Cc: bldg-sim at lists.onebuilding.org
Subject: Re: [Bldg-sim] 90.1-2013 vs 2015 IECC Performance Path Compliance

I just did a little seminar on this very topic for our Rocky Mountain ASHRAE tech conference last week.  There are a few other key differences in 90.1:

- Mandatory occupancy and daylighting controls in parking garages
- Bi-level occ sensors required in stairwells
- Slightly more stringent cooling efficiency requirements (full load and part load, also slightly lower economizer thresholds). Differences in heat pumps as well I believe.
- More stringent envelope requirements (walls and windows). Also note limits to E/W glazing which may require that you rotate/average the baseline.

Other important items to note:

- A90.1 has MANDATORY electrical submetering requirements (separate monitoring for lighting, receptacles, and HVAC, plus some whole-building requirements) -- this is a biggie. Read section 8-Power thoroughly!
- You CAN take credit for renewable energy (up to 5%)
- A90.1 does not have the same commissioning requirements
- A90.1 allows extra lighting credit for room geometry adjustments and some extra lighting controls (see control factor table), whereas IECC does not

This is not a comprehensive list but those are the big ones that jump out.  Whichever method you choose, make sure you are using the space-by-space method for lighting (it will almost always come out better than whole-building).

Cheers,
Elizabeth

Elizabeth Gillmor  PE, BEMP, LC, LEED AP

e n e r g e t i c s  consulting engineers, llc
energetics-eng.com<http://energetics-eng.com> | 303.619.0091

On Mon, May 2, 2016 at 11:08 AM, Duggin, Cory via Bldg-sim <bldg-sim at lists.onebuilding.org<mailto:bldg-sim at lists.onebuilding.org>> wrote:
Does anyone have experience showing code compliance via the performance path in 90.1-2013 vs 2015 IECC?  I have a project that isn’t meeting the 15% threshold against the 2015 IECC standard reference design (per C401.2(3)).  I have always thought the 15% was to level the compliance paths, but the main difference I am finding between the 2015  IECC SRD and 90.1-2013 budget building is the mandatory plug load control requirement.  What am I missing to account for the 15% difference?

Thanks,

Cory Duggin, PE, LEED AP BD+C, BEMP
Principal/Energy Modeling Wizard
TLC Engineering for Architecture
6 Cadillac Drive, Suite 200
Brentwood, TN 37027-5080

direct:

615-346-1939<tel:615-346-1939>

website:

www.tlc-engineers.com<http://www.tlc-engineers.com/>

_______________________________________________
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<mailto:BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20160502/a3b305f6/attachment-0001.html>