I had been periodically working on this article for a while and had made good progress on it. Then, this last week, I attended an energy conference in Portland, Oregon. One comment resonated above all the others made during the conference: “Why do we bombard our customers with facts? They DON’T CARE!! They either like the light or they don’t. CRI? What the heck is CRI, anyway? Does anyone actually know the IESNA (Illumination Engineering Society of North America) definition?” I was attending a session on LED lighting, where the technology stands now and where it’s going in the next couple of years. Prior to this session, I had planned to give a lot of detail on the science of lighting, phototopics versus scotopics, how the color rendering index affects our ability to see color. I even toyed with the idea of giving a tutorial on how to use Visual Basic, which is a free lighting design software. This one comment made me realize all that information was really just a lot of useless noise to most people. Honestly, it’s not how I did the lighting design of my shop, either. It all really boils down to buying a few light fixtures at either a hardware store, big box retailer, or an electrical warehouse and trying them out in your shop to see what you personally like. Keep the receipts, in case you want to try something else.
There are three basic technologies to choose from right now for the main, or ambient lighting. There are high performance T8 or T5 lamp and ballast combinations, or LED. As far as longevity, LED is the winner in this category, although the cost of a LED tubular lamp or an entire LED troffer, which is the basic two foot by four foot fixture you see in most office buildings, is still quite expensive. T5 systems are an option, but I generally don’t recommend them for heights less than 15 feet, due to their intense output and subsequent glare they create at lower levels. My suggestion would be to go with a T8 system. They are the least expensive of the choices, have a really great life of around 30,000 hours and are easy to get your hands on.
The main factor to consider in your lighting design is color. Kelvin is how the color of light is measured. It not only is a factor in things like productivity, it also helps keep or inhibit our circadian rhythms. Early in the morning, as the sun rises, the color is close to 2700 Kelvin. As the day goes on the Kelvin temperature rises into the 5000 – 10,000 Kelvin range, then falls again toward 2700 for our beautiful sunsets. The perfect office environment will probably someday mimic the exterior conditions, but today most offices employ 4100 Kelvin lamps. For extended periods of sedentary work, this seems to be what most lighting designers have chosen. Enough “daylight effect” without making us antsy. For work such as we do in the shop, a higher color temperature is more beneficial. Not only does it promote activity, but we see detail much better in the 5000 to 6000 Kelvin range. Any higher than that and the color goes very blue. Some may like that, but it’s not to my tastes. Also don’t neglect reflectance, or basically, the color of the surfaces that will reflect the light. Without sheeting your shop in stainless steel or some other extremely reflective material a white wall will provide your best reflectance. Again, it’s a matter of taste. As long as you keep the surfaces on the light side, you should be fine.
Lighting is one of those areas that, while there are general rules of thumb, the reality is everyone perceives light and responds to the different attributes differently. There is no one size fits all solution. As we age, our ability to see detail decreases and therefore a white light is beneficial. I currently have 4100 Kelvin lamps in my shop, but will be biting the bullet and changing everything out to a 5000 Kelvin weighted lamps.
Before you buy anything, consider your space and the tasks you intend to perform within that space. Generally, you’ll want one type of light for ambient lighting and some type of spot lighting for detailed tasks. Examples of some different scenarios for ambient lighting would be ten foot ceilings versus seven foot ceilings. If you have a greater ceiling height, the fixture will allow the light to spread more before it hits the working surface, which is generally about three feet off the ground. So, you will probably want a higher lamp count fixture and will space them further apart. Inversely, if your ceiling height is only seven feet, you will likely be happier with a one or two lamp T8 fixtures and have more of them spaced closer together. In my shop, I found I could negate shadows in the general work area by spacing my four lamp fixtures ten feet apart, on center. Here are some general suggestions:
Less than 10 foot ceilings | 2-lamp T8 fixtures
10-15 foot ceilings | 4-lamp T8 fixtures
15 foot and higher ceilings | 6-lamp T8 fixtures or 4-lamp T5 fixtures
Buy at least two fixtures for testing purposes and hang them up in a temporary fashion and see how far apart, or close together you need to place them to avoid creating shadows.
If you’re purchasing T8 lamps and ballasts at big box store, you may find it difficult to get a quality lamp. I got general service fixtures at Lowes (4-bulb version pictured left). I opened a fixture to make sure it was of quality, but had to purchase my lamps at a electrical warehouse. Your experience will differ depending on how big a city you’re in. I strongly suggest checking the lamp and/or ballast against the approved list. With today’s smart phones, this is easy to do at the time of purchase. If you’re purchasing T5s, you’re in luck. I’ve yet to see a T5HO (High Output) that doesn’t meet our program requirements. If you’d like to go down the LED route, you have three lists to check. LightingHouseLab.com, which will list lamps and fixtures that have not yet been approved on this list. And finally EnergyStar.gov.
For task lighting, I would just head straight over to the LED aisle. I’ve never been a fan of compact fluorescent lamps (CFL) and incandescents are being phased out. You can still get 60 watt lamps, but they go away in 2014. Pricing has come down by more than half in the last two years and LEDs are becoming more cost effective each day. Cree just released a really nice “A” lamp (looks like a standard incandescent bulb). It is a remarkable bulb. Unfortunately, you will not find this on the Energy Star site. The reasons are inconsequential and serve no purpose for this article, but I can tell you first hand it is a really nice lamp.
I primarily use the old swing arm lamp fixtures. I tried the clamp on type and I purchased several cheap swing arm fixtures before I found this site, which sells a sturdy fixture with metal gussets at the pivot points. Although what is pictured is blue, I have white and stainless models. I employ a simple holder that allows me to move them along the French cleat system, but be creative. After all, we are woodworkers, right!?! Enjoy your well lit shops!
Vic Hubbard is the Commercial, Industrial and Agriculture Energy Services Specialist for Franklin PUD in Pasco, WA. A core function of his service is in the implementation of non-residential lighting programs. He currently serves on the Northwest Energy Efficiency Alliance’s (NEEA) Commercial Upstream Lighting Advisory Board. He is an amateur woodworker, photographer, and blogger. Check out his site Tumblewood Creations or find him on Twitter at @Tumblewood.