integrated design lab - bozeman

Billings Valley Federal Credit Union—Custer Branch Integrated Design Lab, Bozeman, MT

Prepared by Evan J. Burnett, LEED Green Assoc. June 6, 2014

Integrated Design Lab High Plains Architects, P.C. Tom Wood, AIA, NCARB Ed Gulick, AIA, LEED AP BD+C Operated by Montana State University 2720 Minnesota Avenue Bozeman, MT 59717 Billings, MT 59103 (406) 994-4934 (406) 896-0250

[email protected] [email protected] www.idlbozeman.com highplainsarchitects.com

The work of the Integrated Design Lab-Bozeman is supported by the Northwest Energy Efficiency Alliance and North Western Energy.

ELECTRIC LIGHTING ANALYSIS

Billings Valley Federal Credit Union—Custer Branch, Billings, MT June 6, 2014

Integrated Design Lab, Bozeman, MT High Plains Architects, PC, Billings, MT

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TABLE OF CONTENTS

Executive Summary 3

General Analysis Procedure 4-6

Results and Recommendations 7

APPENDIX— Illuminance Calculations and Iso-Footcandle Charts

Option 1A—28 T5 Fixtures [single lamp] 8

Option 1B-1—28 T5HO Fixtures [single lamp, high output] 9

Option 1B-2—40 T5HO Fixtures [single lamp, high output] 10

Option 1C—28 T5 Fixtures [double lamp] 11

Option 2A—26 T5 Fixtures [single lamp] 12

Option 2B—26 T5HO Fixtures [single lamp, high output] 13

Option 2C—26 T5 Fixtures [double lamp] 14



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EXECUTIVE SUMMARY This analysis investigates the electric lighting potential of two different luminaire configurations for the Billings Valley Federal Credit Union—Custer Branch, located in Billings, Montana. Electric lighting analysis is supplementing the daylighting analysis previously issued [May 15, 2014]. As directed by Ed Gulick of High Plains Architects, PC, we were provided with two general lighting options. Those options are as follows: OPTION 1: 28 T5 Fixtures [single lamp] oriented along the N/S lobby beams OPTION 2: 26 T5 Fixtures [single lamp] oriented E/W along the edge of the lobby walls We expanded the options to include variations on the number of lamps and type of lamps in order to understand a broader set of possibilities. Those options are as follows: OPTION 1A: 28 T5 Fixtures [single lamp] oriented along the N/S lobby beams OPTION 1B-1: 28 T5HO Fixtures [single lamp, high output] oriented along the N/S lobby beams OPTION 1B-2: 40 T5HO Fixtures [single lamp, high output] oriented along the N/S lobby beams and N cove OPTION 1C: 28 T5 Fixtures [double lamp] oriented along the N/S lobby beams OPTION 2A: 26 T5 Fixtures [single lamp] oriented E/W along the edge of the lobby walls OPTION 2B: 26 T5HO Fixtures [single lamp, high output] oriented E/W along the edge of the lobby walls OPTION 2C: 26 T5 Fixtures [double lamp] oriented E/W along the edge of the lobby walls Both sets of options were simulated through AGI32 using a basic 3D surface model. The following pages present a summary of the simulations. The appendix contains the calculation grids and illuminance values. The analysis focuses on the work plane height of the teller stations, check stand, and other lobby functions. Calculation points were spaced 2’-6” apart from each other in an orthogonal grid. Calculation grids were located at 3’-6” above the floor in the lobby [takes into account for cabinetry and solid surfacing heights from Revit model such as the teller stations and check stand] and at 2’-6” above the floor in the offices and support spaces.



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GENERAL ANALYSIS PROCEDURE The Revit model, provided by Ed Gulick of High Plains Architects, PC, was simplified using Revit Architecture 2014 to remove unnecessary fixtures, surfaces, and so forth. The Revit model was then exported into AGI-32 for daylighting analysis. Simulations were conducted for each of the seven electric lighting options. The surface conditions and material reflectance are listed in the table below. Achieving illumination levels of approximately 30 fc in the lobby was the metric to determine the adequacy of each electric lighting option.

Object: Reflectance: Type: Definition:

Ceilings 70% Interior Double Sided Grey

Walls 50% Interior Double Sided Grey

Monitor Walls 75% Interior Double Sided Grey

Floor 30% Interior Double Sided Grey

The 3D model surface properties as defined in the lighting program AGI-32 are as follows:



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SM-128T5

Polar Candela Curves Describing General Aiming

GENERAL ANALYSIS PROCEDURE

OPTION 1: T5 Fixtures Manufacturer: Cooper Lighting Brand: Metalux Fixtures: SM-128T5 [single lamp] SM-228T5 [double lamp] Reflectors: Symmetrical

OPTION 2: T5 Fixtures Manufacturer: Cooper Lighting Brand: Metalux Fixtures: SM-128T5 [single lamp] SM-228T5 [double lamp] Reflectors: Asymmetrical

OPTION 1/2: T5HO Fixtures Manufacturer: Cooper Lighting Brand: Metalux Fixtures: SSF-154T5 [single lamp] Reflectors: Direct-Indirect

Fixture Descriptions

SM-228T5

SM-128T5 SM-228T5

SM-154T5 SM-154T5

Typical Details *

Option 1

Option 2

*The fixtures were modeled according to the detail concept sketches enclosed by Ed Gulick [above].



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Option 2 Lobby Lighting Plan

OPTION 1: 28 T5 Fixtures Along N/S Beams OPTION 2: 26 T5 Fixtures Along E/W Coves

GENERAL ANALYSIS PROCEDURE

N

S1

S1

S1 Option 1 Section Through Lobby

Option 1 Lobby Lighting Plan

*The indirect fixtures were spaced according to the sketches enclosed by Ed Gulick [above]. Fixtures are located 9’-7” above finish floor in both schemes, and aim upwards towards the ceiling [approximately 5’-6” away].

N S1

S1

S1 Option 2 Section Through Lobby

Option 1B-1 Strip of 12 Fixtures along the N Cove

Option 1B-1 Strip of 12 Fixtures along the N Cove



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RESULTS AND RECOMMENDATIONS Overall, we recommend selection of Option 1B-2 [40 T5HO fixtures, high output] for the lobby space of the Billings Valley Federal Credit Union—Custer Branch. Both of the initial combinations [Options 1A and 2A] did not provide the general illumination of 30 footcandles required for lobby functions. Key to understanding this result is the distance the light has to travel up to the ceiling in order to bounce off the surfaces back down into the lobby. The distance of approximately 5’-6” reduces the amount of reflected light dramatically. To address this issue, the initial combinations were expanded to include high output fixtures and double lamp fixtures. Options 1C and 2C [T5, double lamp] both exceeded the level of adequate general illumination to an excessive degree, with footcandle values in the upper 30’s to 40’s. Options 1B-1 and 2B [T5HO, single lamp, high output] provided relatively adequate general illumination, but had values below 30 footcandles at the teller stations. In order to boost the teller station illumination levels, a strip of 12 T5, high output fixtures was added along the north cove [Option 1B-2]. This option provided the best general illumination, which has footcandle values ranging from the high 20’s to mid 30’s. Enclosed are the iso-footcandle charts detailing the simulations for review. Please contact us for further discussion of these simulation results and other possible design considerations. These recommendations should be verified and confirmed by the electrical engineer on this project.

OPTION 1B-2: 40 T5HO Fixtures Manufacturer: Cooper Lighting Brand: Metalux Fixtures: SSF-154T5 [single lamp] Reflectors: Symmetrical [28 N/S beam fixtures] Asymmetrical [12 E/W cove fixtures]



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APPENDIX Option 1A—28 T5 Fixtures [single lamp] Iso-Footcandle Chart



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APPENDIX Option 1B-1—28 T5HO Fixtures [single lamp, high output] Iso-Footcandle Chart



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APPENDIX Option 1B-2—40 T5HO Fixtures [single lamp, high output]* Iso-Footcandle Chart

*This is the recommended option



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APPENDIX Option 1C—28 T5 Fixtures [double lamp] Iso-Footcandle Chart



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APPENDIX Option 2A—26 T5 Fixtures [single lamp] Iso-Footcandle Chart



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APPENDIX Option 2B—26 T5HO Fixtures [single lamp, high output] Iso-Footcandle Chart



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APPENDIX Option 2C—26 T5 Fixtures [double lamp] Iso-Footcandle Chart

integrated design lab - bozeman

Documents

lobby walls option

ns lobby beams option

high output oriented

mt high plains architects

n cove option

lobby functions

integrated design labbozeman

general lighting options