Lighting for Layout?

[Gary S]

Wayne: thank you for the detailed commentary. Gives me alot to think about, and more things to discuss with The Gauge et al!

Gary, unless you've got different terminology in Texas, isn't a 2x4 fixture a pair of four foot tubes?

We've always used the dimensions of the fixtures... 2x4 is a two foot by four foot fixture. A 1x4 would be a 1 foot by four footer. A 2x2 is a square two foot by two foot. Now, the two foot by four foot fixtures can be had in a 2, 3, or 4 lamp variety. So, the fixture I mentioned would be called a 2x4 4-lamp fixture. That's the Texas way!

That's about 2.3 watts per square foot, but if I were re-doing it, I'd modify the spacing of the fixtures somewhat to include another two fixtures.

So you would be pushing 3 watts per square foot? I was thinking the 3 watts would be good, but am relying only on anecdotal evidence.

For your situation, though, I think that placing the lighting over the layout will give you more bang for your lighting buck. If possible, position the lights slightly closer to the viewing side, rather than directly over the centrepoint of the layout. Don't place them above the aisles, as you'll end up with head shadows on the layout.

I didn't think about shadows from my head. I need to consider that. I will do a little diagram of my area and thoughts so we will have a better idea of what we are dealing with... I'll post that shortly.

Because of the need to keep the lights over the layout, you might want to re-think placing them between the joists, and instead place them beneath the finished ceiling. If you want recessed lighting, avoid a finished (drywalled) ceiling altogether and install a suspended ceiling.

I had definitely considered a suspended ceiling and actually prefer that over sheetrock. It would make everything so much easier. No fighting a 70 pound sheet up to the joists with one hand while running the screwgun with the other. hock: No taping and floating! No painting! And easy installation of lighting and such. Plus easy access if I ever needed to do any wiring or anything else above the ceiling.

However, I have some major concerns in using the suspended ceiling to seperate the "living" space from the attic space. I'm not sure how attics are done up north, but down here we have to maintain a flow of outside air through the attic. This is typically done by using vented soffits at the eaves and either a ridgeline vent or a metal ventilator near the highpoint of the roof. So far so good. But with the humidity that we typically have all year long, I am afraid that the tiles would have issues. They would absorb the moisture and start sagging, and turn brown. I did some checking on a lay-in ceiling manufacturer's website and they didn't recommend their product for an installation between living space and a ventilated attic. They said the tiles should only be used in environmentally controlled areas such as that between a first floor and a second floor, or between a basement and a first floor.

Secondly, I need the ceiling joists for the integrity of the structure. I could hang the suspended ceiling below the joists, but I want the ceiling to be at least 8 feet tall. And I don't want to go with longer wall studs, because then the building would be taller than my house. And, considering the first point above, I may still need the sheetrock above the tile to separate the tile from the outside air.

Also, I need to insulate between the attic and the living space. Not sure if it would be okay to lay the insulation on the tiles.... probably would be okay, but still have the issues above.

Down here, the suspended ceiling system is used almost exclusively in concrete or metal structured commercial buildings. I have never seen it used as a seperation between a ventilated attic and living space. And that makes me sad because I really really prefer the suspended ceiling.

Even if you want to install the lights between the joists, a four tube fixture is going to be too wide for most joist spacings.

I would have to take the fixture size/placement into account when I install the joists. I would have to build the recesses into the framework.

The other change that I'd suggest is to use 40 watt tubes instead of the 32s - despite what they try to tell you, 32 watts does not (can not) produce 40 watts worth of light.

I had a mild surprise about 6 months ago. I am an electrician by trade, but haven't been in construction for over ten years. Well, we needed some new fixtures for a lab, so I called the supply house and ordered some 2x4 2-lamp T12 lay-in fixtures. The salesman said that they don't even make those fixtures anymore. Everything has gone to the smaller diameter T8s. And I'll have to check, but I think the T8s have a max of 32 watts. And that is with the electronic type ballasts instead of the old electromagnetic ballasts. Again, some research is in order... on both the wattage and the colors available as per your discussion.

Do you have T8s or the older T12s? The "8" stands for "eigths" of an inch, so a T12 is 1.5 inches in diameter, a T8 is only 1" in diameter.

Whatever you decide, I agree with your statement: you can't have too much light.

Light is good!