I am builing a 30x30x10 garage/shop. Lowes has 2 bulb 4 foot T-8 32
watt lights on clearance for 15 bucks. They also have 2 bulb 40 watt
fixtures for 10 bucks.
The T-8's have electronic ballasts.
How many lights do you think I need and will I be happy with the light
of the T-8's? I was thinking of 9 lights but am open to suggestions.
WIll the T-8's be that much dimmer than the 40 watt ones?
Those $10 shop lights come with a cord and plug for a reason. They may
not last long and the cord makes them easy to replace.. Actually I
have some that are 20 years old, I have also had others crap out in a
I put 4" boxes in the ceiling with two duplexes and 4 lights plugged
into each one.
It's perfectly acceptable to install outlets in the ceiling, if you look
at most of the lighting in warehouses and such they're done like that to
enable easy removal of the fixtures for cleaning or replacement, or
disconnection in case of a fault.
The $10 fixtures are really cheaply made though, a decent ballast alone
costs at least $15. A $25 fixture is 10 times as good as a $10 one.
What about these 15 dollar T-8's? Even though they have a plug, do you
think they are ok?
Also, I live out in the country. Because I am doing this myself, I am
thinking of using OSB for the walls and ceiling. What do you think?
(Painted gloss latex white.)
Hard to say without looking at it. Feel the fixture, does it feel
flimsy? Look at the sockets in particular, cheap flaky sockets will
haunt you. If the ballast says high power factor, then it likely is at
least decent. The electronic ballasts without power factor correction
are the cheapest of the cheap, and they tend to not last long. It's not
because of their lack of PFC that they fail, but it tends to come with
the territory. I've been rather pleased with the Advance Centium instant
start T8 ballasts. They're inexpensive, about $15 for the ballast, and
have proven to be quite dependable. I've even used them for a lot of
things they were never designed to do, like power low pressure sodium
lamps, mercury lamps, various fluorescent lamps, even drive small Tesla
coils and such and have yet to blow one up by this abuse.
No idea about the walls and ceiling, that's a personal preference, my
expertise is in lighting and electronics. If you find you need more
light, it can always be added later. Likewise if you end up with too
much, you can plug some fixtures into separate switches.
T8s are significantly brighter than 40W T12s, partly because magnetic
ballasts tend to under-run the lamps pretty significantly, and partly
because there are advantages to running fluorescent lamps on high
frequency that are rather complex in detail, but the result is you get
more light per watt, as well as no perceptible flicker.
There is a lot more to it than that too, there are many different
phosphor compositions with widely varying characteristics. Most T8s use
a trichromatic blend which is much more efficient and has much better
color rendering than the old halophosphates. Look at the type number on
the tube, it will be something like this:
Which translates Fluorescent, 32W nominal, Tubular, 8 8ths inch
diameter, 80+ CRI, 3500K color temperature.
I recommend 80 series which are 80+ CRI, which compares nicely to the 53
CRI of old fashioned Cool White. The higher the color temperature, the
more bluish the light. I personally like 5000K and 6500K daylight best
for utility lighting but some prefer the warmer lower temperatures.
You can buy premium T12s with trichromatic phosphors, and you can get
electronic T12 ballasts, but it's all a lot more expensive than T8 with
no real gain.
Do splurge for some decent fixtures though, the really really cheap ones
have lousy ballasts that are low power factor and like to burn up.
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