Dear Cherry,

I love your books and have several, on both barn/facility planning and arena work, thanks for your excellent instruction.

I have a 36'x36' barn with 4 stalls, washrack, and tackroom, with a raised center aisle. We installed halogen flood lights over each stall/room, and in the corners of the aisle. While it gives a lovely golden glow to the barn, the dark shadows and uneven lighting it creates are terrible to work in. I'm considering installing fluorescent shop lights, possibly 8' long. To achieve the most even and bright lighting, would you recommend placing the fluorescent lights up in the apex of the roof, center and parallel to the barn aisle, or perpendicularly across the aisle every 12 feet?

Thank you for your help. We've already made one costly mistake and I'd like to get it right this time!

Molly E.

Dear Molly,

Richard, my husband and co-author of Horse Housing and producer of our DVD Your Horse Barn, will answer this one.

Hi Molly,

As you've found, quartz halogen lights can produce bright light with a nice color but they can also produce harsh shadows depending on the number of lights and where they are located. Placing halogen lights in two or more corners of a stall or aisle or other space rather than directly overhead can help provide more even lighting.

Flourescent lights provide a diffused light that is more even, plus they don't get anywhere near as hot at halogen lights. They work best if left on for long periods without being turned on and off frequently and they are typically brighter after warming up for a few minutes.

Ballast

Unlike halogen or regular incandescent light bulbs, fluorescent lights need a ballast to start the lamp and regulate current when it is on. There are basically two types of ballast: magnetic and electronic.

Magnetic ballasts are the oldest type and include preheat, rapid-start, and instant-start. These ballasts use a magnetic core of several steel plates wrapped with aluminum or copper windings. Preheat fixtures have a separate starter that jump-starts the lamps with an extra boost of electricity. The most common preheat fixtures, like shop lights, use two 1 ½" diameter 4-foot long 40 watt tubes called T12 that have a two-pin cap on each end. These fixtures are readily available and work well down to 50°F. Below that temperature, however, they can dim appreciably, flicker, and be difficult to start.

Electronic ballasts use solid state circuitry instead of a magnetic core. They cost about 1 ½ times as much as magnetic ballasts but are smaller, quieter, cooler, less prone to flicker, cost less to operate and work better in colder temperatures. Some will hold 4 lamps instead of just two and some can also be used with a dimmer switch.

Color

The apparent color output of fluorescent lamps varies widely. Some lamps will give an eerie whitish cast to a horse's gums - a distinct drawback when your trying to assess the health of a horse's mucus membranes! Other types can make objects appear pinkish or bluish.

There are many marketing names used to describe fluorescent lamps. Cool White lamps are the most commonly used and have more green in the light. Warm White lamps have more red and orange light, and are designed to mimic light produced by incandescent lighting. Daylight lamps have a blue tint similar to the color of light reflected from a clear sky.

The apparent color of a light bulb or lamp is designated by its Kelvin or "K" rating. The following table will give you an idea of how Kelvin designations relate to the real world:

Placement

Fluorescent lamps project light perpendicular to the tube, so installing them in a line parallel to the barn roof peak would light the aisle and throw light sideways into the stalls, particularly the stall fronts. Spacing of the lights will depend on the fixtures you choose.

Depending on the fixtures you choose, the height of the lights (they should be a minimum of 11 feet high for safety), and how light-colored and reflective the walls and ceiling are, the backs of the stalls may be in shadow. So you might consider a fixture over the back of each stall for more even lighting.

Also, consider using 240 watt instead of 120 watt fixtures. 240W fixtures will use less amperage so you can run more fixtures per circuit. Some units allow installations at either wattage.

I suggest that you visit other barns in your area to how their lighting works and to discuss you plans with a local lighting designer or retailer.

Here's a clip from our video, Your Horse Barn, that tells how fluorescent lights work.

Best of Luck,