Skip to main content


Open Main MenuClose Main Menu

Group Relamping For Cost Savings and Better Lighting Quality


  • Lamp: The standard term that lighting industry uses for  light bulb. Lamp is another word for light bulb.
  • Relamping: The act of replacing bulbs when they burn out.
  • Group relamping: Strategic maintenance practice where large numbers of bulbs are changed out on a predetermined schedule.
  • Fixture: The enclosure that contains the lamp(s); includes the reflector, ballasts, clear cover, etc.


Operating and burned out lamps in an arena

Lamp is another word for light bulb.

Group relamping is effective for large amounts of lighting.

Photo illustrates a mix of operating and burned out lamps in an arena.

Save time and money with group relamping.




Large facilities with many overhead lights constantly need to replace burned out lamps. Changing lamps takes time. One or two workers using a lift may spend a great deal of time changing lamps in high overhead fixtures. Small businesses may need to rent lift equipment to replace burned out lamps. Ignoring burned out lamps degrades the quality of a facility’s lighting and therefore impacts the work environment. Often, routine cleaning of lamps and fixtures is neglected. This compromises light quality and quantity.




Consider group relamping, a maintenance practice where large numbers of lamps are replaced at the same time. This practice can be used to efficiently maintain lighting in arenas, warehouses, production facilities, aircraft hangers, schools, office buildings, places of worship, and other large businesses. Group relamping is effective when lamps are the same kind (usually fluorescent). It is also useful when switching out all of one type of lamp to another (retrofit).




All lamps have a specified “average life” in hours. This is the point where 50% of the lamps have burned out. Lamps do not burn out at a steady rate over their lifetime – they tend to start to fail at once. For example, if 70% of the “average life” is chosen as a point in time, almost all of the lamps will still be working but getting near the time where many will start to fail.


The main advantages of group relamping are:

  • Fewer numbers of burned out lamps
  • Lower labor costs per lamp
  • Increased worker safety with less time on a ladder or lift
  • Easier and less disruptive lighting maintenance
  • Lower costs: Lamps are bought in bulk
  • Easier lamp disposal planning


Here’s how group relamping can save money…

Example: An office operates lamps for 3,500 hours per year. There are 400 fixtures with four F32T8 lamps per fixture (1,600 lamps total). Average lamp lifespan is seven years.

25,000 hours  ÷ 3,500 hours used per year  =  7 years


After a few years, lamps would begin to burn out and need replacing:

1,600 lamps ÷ 7 years  =  229 average annual spot relampings


 If we group relamp at 70% of average life, we replace more lamps at once but experience minimal burnouts and lower labor costs. Why? The lamps are replaced all at once before they start to fail.


70% x 7 years = 4.9 years (relamp all 1,600 lamps every 5 years)



Table: Side-by-side comparison of spot versus group relamping


Spot relamping



Group relamping 



Hourly wage


Time per lamp

(access,replace, clean) 25 minutes


Hourly wage


Time per lamp

(access, replace, clean) 6.2 minutes


Lamp Costs

229 lamps per year × $3 per lamp = $687 per year

Labor costs

229 lamps per year × $8.33 per lamp = $1,910 per year


Lamp costs

1,600 lamps every 5 years × $3 per lamp = $4,800 every 5 years

Labor Costs

1,600 lamps every 5 years × $2 per lamp = $3,200 every 5 years


   Total costs

Spot relamping costs (lamp + labor)
= $2,597 per year

This is equal to $12,985 every 5 years


Total costs

Group relamping costs (lamp + labor)
= $1,600 per year

This is equal to $8,000 every 5 years

Cost savings of group vs. spot relamping over a 5 year period: $4,985
Note: Savings may be reduced if there is a cost associated with disposal and recycling.




  1. DiLaura, D. L., Houser, K. W., Mistrick, R. G., & Steffy, G. R. (2011). The Lighting Handbook (10 ed.). New York, NY: Illuminating Engineering Society.
  2. Doty, S., & Turner, W. C. (2009). Energy management handbook (7th ed.). Lilburn, GA: The Fairmont Press, Inc.
  3. ENERGY STAR. (2006). Buildings and Plants: 6. Lighting. Retrieved September, 2012, from
  4. Pustinger. (2012). Lighting Management & Maintenance, 40, 34l35.
  5. US Department of Energy. (2010). Exterior lighting guide for federal agencies. Washington, D.C.: Author.
  6. Wood, D. (2004). Lighting upgrades: A guide for facilities managers.
    Lilburn, GA: The Fairmont Press, Inc.



  1. R. Scott Frazier, Ph.D., PE, CEM, Assistant Professor and Extension Energy Management Engineer, Biosystems & Agricultural Engineering
  2. Paulette Hebert, Ph.D., Professor, Design, Housing & Merchandising
  3. Gina Peek, Ph.D., Assistant Professor and Extension Housing & Consumer Specialist, Design, Housing & Merchandising



  1. Dana Baldwin, Oklahoma Cooperative Extension Service
  2. Dan England, Oklahoma State University
  3. Recia Garcia, Oklahoma Cooperative Extension Service
  4. Jim Rhodes, Oklahoma Cooperative Extension Service
Was this information helpful?
Fact Sheet
Light and Fading: Choose Lighting to Limit Fading in Your Home

An explanation of how light can fade items in your home and preventative measures you can take to limit this fading.

Home Care & SafetyHome Energy SavingLighting & Decor
Fact Sheet
Safe and Sustainable Lighting

Learn about the different types of lightbulbs, how they work and how to choose the best bulb for the home.

Home Care & SafetyLighting & Decor
Fact Sheet
Light Pollution

A summary of what light pollution is, how it can be harmful and what to do to reduce it.

Home Care & SafetyHome Energy SavingLighting & Decor
Fact Sheet
Sustainable Security Light

Understand the benefits of proper security lighting based on costs, needs and personal preference and compare the different types of outdoor security lights.

Home Care & SafetyHome SafetyLighting & Decor
Back To Top