[Equest-users] dwelling unit / residential LPDs

[Joe Snider]

Wow.  Fantastic dialogue everyone, and greatly appreciated.

 

It sounds like the strategy we used has been approved on multiple projects
in the past, but in our case has been denied.  

 

To recap, we did Space-by-Space Method, using 1.1 w/sf for baseline in
living / bedrooms and our specific hardwired fixtures for our proposed.  

 

In the denial, reviewer referenced "a CIR" which we can only assume was the
2/23/2007 CIR referenced by some here, and reviewer told us we needed to
model all dwelling unit lighting as 1.1 w/sf for both proposed and baseline
(without distinguishing between plug-ins and hardwireds).

 

While we feel that our method was pretty reasonable, we'll likely appeal
under that CIR which opens the door for exceptional calculations.

 

Anyway, something to keep in mind for others in the future.  As we all know,
LEED reviews are not created equal..

 

Thanks again for all of the help.  I hope I can reciprocate with as much
value in the future.

 

Sincerely,

 

Joe Snider

 

---

Joe Snider, AIA, LEED AP

 

SEQUIL Systems, Inc.

high performance sustainable structures

 

1 SE 4th Ave, Suite 205

Delray Beach, FL 33483

t: 561.921.0900

f: 561.208.6090

 

www.SEQUIL.com

 

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Maria
Karpman
Sent: Wednesday, December 08, 2010 5:04 PM
To: 'Bishop, Bill'; 'James Hansen'; 'Aleka Pappas';
equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] dwelling unit / residential LPDs

 

Since lighting inside dwelling units is not in scope of ASHRAE 90.1 (section
9.1.1 exception b), the multifamily allowance in Table 9.5.1 applies to all
areas in multifamily buildings except apartment units (corridors,
stairwells, lobbies, mechanical rooms, etc.). 

 

IECC 2009, which is adopted as state code in many locations, modified
in-unit lighting exception to include apartments (see quote below). 

 

SECTION 505

ELECTRICAL POWER AND LIGHTING SYSTEMS

(Mandatory)

505.1 General (Mandatory). This section covers lighting system

controls, the connection of ballasts, the maximum lighting

power for interior applications and minimum acceptable lighting

equipment for exterior applications.

Exception: Lighting within dwelling units where 50 percent

or more of the permanently installed interior light fixtures

are fitted with high-efficacy lamps.

 

Because of the change, the multifamily allowance of 0.7 W/SF in IECC Table
505.5.2, which is otherwise aligned with ASHRAE 90.1 Table 9.5.1, now
includes lighting in apartment units in addition to common spaces. 

 

There was a LEED CIR from 3/23/2007 that allowed 2 W/SqFt LPD baseline for
in-unit lighting which we used successfully in several LEED 2.1 submittals,
but I think it would be silly for USGBC to continue allowing 2 W/SF baseline
for LEED 3.0 because is so much worse than many local codes.  

 

I'd use one of the following options for documenting in-unit lighting credit
for LEED 3.0:

a)      Use 0.7 W/SF in-unit lighting in the baseline model. In the proposed
model, keep this allowance unchanged for areas with no hard-wired lighting
(living rooms, bedrooms, etc.), and use the actual LPD for areas where
lighting is specified (kitchens, bathrooms, etc.). Reference IECC in LEED
submittal as the source for the baseline. 

b)      Use 1.1 W/SF baseline based on LPD for Hotel/Motel/Dormitory from
Table 9.6.1. In proposed design, keep 1.1 W/SF for areas with no specified
lighting, and use the actual LPD for areas where lighting is specified. 

c)       Use LPD for spaces of appropriate type from Table 9.6.1 (restrooms,
corridors, etc.)  in the baseline model, and the actual specified lighting
in the proposed design.

   

Either way you go, you should watch for situations when specified lighting
is intended only for part of the room. For example, if there is a hard-wired
fixture in the dining area of dinging/living room, you should not assume
that this will be the only fixture in the space when calculating proposed
LPD. 

 

Maria 

 

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Bishop,
Bill
Sent: Wednesday, December 08, 2010 3:54 PM
To: James Hansen; Aleka Pappas; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] dwelling unit / residential LPDs

 

There is an exception to the scope of section 9.1.1, for "lighting within
dwelling units". However, in addition to the 1.1 W/ft2 allowance for
hotel/motel guest rooms and dormitory living quarters in the space-by-space
method, there is the 0.7 W/ft2 allowance for "multifamily" using the
building area method (Table 9.5.1). This seems to be another area where the
Standard is vague. Many of my projects have been dormitories, which do not
contain "dwelling units" as defined in section 3, since the residence spaces
don't contain kitchens. So I have not had to apply this exception yet.

 

Bill

  _____  

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of James
Hansen
Sent: Wednesday, December 08, 2010 3:43 PM
To: Aleka Pappas; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] dwelling unit / residential LPDs

 

Is there a CIR or something that says that residential LPD is unregulated?

 

Table G3.1 is pretty specific about residential unit lighting for the
proposed model (see below):

 



 

As long as the lighting is shown on building plans and permanently wired,
you are allowed to use the actual lighting power.   I have done 10+
residential projects where we've listed 1.1 W / sq ft for the living /
bedroom areas for the baseline building, and used the actual density for the
proposed model, and been approved.  There certainly isn't anything wrong
with doing it the ECM route, but where, specifically, does it say you can't
take credit for any residential unit lighting efficiencies?  

 

GHT Limited
James Hansen, PE, LEED AP

Senior Associate

1010 N. Glebe Rd, Suite 200

Arlington, VA  22201-4749

703-338-5754 (Cell)

703-243-1200 (Office)

703-276-1376 (Fax)

 <http://www.ghtltd.com/> www.ghtltd.com

 

 

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Aleka
Pappas
Sent: Wednesday, December 08, 2010 3:25 PM
To: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] dwelling unit / residential LPDs

 

That 1.1 W/SF from section 9 doesn't apply to apartment or condo dwelling
units.  Residential unit LPD is unregulated.  We calculate savings for
residential lighting as an exceptional calculation using a baseline LPD
sited from research (which is kind of all over the place), and calculate
savings for installed lighting systems that provide for full illuminance in
specific spaces in the residential units.  The lighting is scheduled on for
750 hours/ year (from an old LEED CIR).  These calcs have been approved in
the past for LEED EAc1 under NC 2.2 and 3.0.

Aleka Pappas

Building Energy Engineer

GROUP14 ENGINEERING, INC. 
Inspiring better buildings. 
1325 E. 16th Ave, Denver, CO 80218 
Direct: 720.221.1082/ Main: 303.861.2070/Fax: 303.830.2016
APappas at group14eng.com
www.group14eng.com

Group 14 is the Carbon Group on the periodic table. Group14 Engineering
offers building energy optimization, LEED coordination, commissioning,
energy audits, LEED EBOM, and greenhouse gas analysis to reduce building and
communities' carbon footprint. 


On 12/8/2010 7:25 AM, Bishop, Bill wrote: 

Joe,

 

The dwelling units exception in Appendix G applies to "spaces in which
lighting systems are connected via receptacles and are not shown or provided
for on building plans." You say you've worked hard to reduce lighting energy
use, so presumably, you've designed the lighting for the spaces and it
appears on the plans. Therefore, you are justified in using your actual
lighting design for the proposed building model, and the LPD value for the
baseline, which should be 1.1 W/ft2 for living quarters per Table 9.6.1.

 

Regards,

Bill

 

William Bishop, PE, BEMP, LEEDR AP | Pathfinder Engineers & Architects LLP

Mechanical Engineer

 

134 South Fitzhugh Street                 Rochester, NY 14608
T: (585) 325-6004 Ext. 114                F: (585) 325-6005

wbishop at pathfinder-ea.com           www.pathfinder-ea.com
<http://www.pathfinder-ea.com/> 

P   Sustainability - the forest AND the trees. P 

  _____  

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
Sent: Tuesday, December 07, 2010 7:16 PM
To: Joe Snider; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] dwelling unit / residential LPDs

 

Hey Joe,

 

If you're looking to start somewhere.  I know the NEC (NFPA 70) lays out a
clear method of estimating dwelling unit lighting loads within Article 220.
It starts off seeming high (3W/SF), but there are heavy demand factors that
vary with the total calc'd load following within the same article: i.e.
first 3,000 @ 100%... 3,000 to 120,000 @ 35% etc.

 

While I've yet to fall back on the NEC as an energy modeling resource, I'm
unaware of any better direct source for residential lighting loads. I
imagine if you dig hard enough, one of the ASHRAE handbooks probably has
something along these lines as well that might give you a different sum.

 

I think ASHRAE Fundamentals does have a clear thing or two to say regarding
what percentage of the lighting load should end up in a space vs. a plenum
when you are talking about different lamp sources (incandescent vs. CFL.) -
something to be aware of if you want to pursue this avenue.

 

~Nick

 

cid:489575314 at 22072009-0ABB

 

NICK CATON, E.I.T.

PROJECT ENGINEER

Smith & Boucher Engineers

25501 west valley parkway

olathe ks 66061

direct 913 344.0036

fax 913 345.0617

www.smithboucher.com 

 

From: equest-users-bounces at lists.onebuilding.org
[mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Joe Snider
Sent: Tuesday, December 07, 2010 5:24 PM
To: equest-users at lists.onebuilding.org
Subject: [Equest-users] dwelling unit / residential LPDs

 

I have reviewed the archives and found a few threads on this topic but
couldn't find either good resolution, or a clear enough string to reply to,
so I thought I would re-post:

 

ASHRAE 90.1 App G doesn't let you include dwelling units in typical LPD
calcs.  They say you need to plug in the same number for both proposed and
baseline.

 

But you can apparently pursue exceptional calcs to justify any cost savings
in LEED.  But you need to show some kind of analysis as to how you chose a
baseline, such as a study or something presumably that shows typical w /sf
for residential.

 

We have worked very hard to reduce energy use in lighting in a few high-rise
residential projects and would like to be able to receive credit for that on
our energy model.

 

Has anyone been through this with USGBC and / or know of a good resource for
a baseline w / sf for residential?

 

In advance, thank you very much.  Great forum.

 

Sincerely,

 

Joe Snider

 

---

Joe Snider, AIA, LEED AP

 

SEQUIL Systems, Inc.

high performance sustainable structures

 

1 SE 4th Ave, Suite 205

Delray Beach, FL 33483

t: 561.921.0900

f: 561.208.6090

 

www.SEQUIL.com

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20101208/53b49585/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 34635 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20101208/53b49585/attachment-0002.gif>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 2412 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20101208/53b49585/attachment-0004.jpeg>
-------------- 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/equest-users-onebuilding.org/attachments/20101208/53b49585/attachment-0005.jpeg>