Most of the primary lighting we’re doing on the first floor renovations comes from cans. Also called “down lights” or “recessed lights”, these are basically wired up just like table lamps, but the housing for your light bulb is in a metal can that’s embedded in your ceiling. Can lights come in a few different sizes and flavors depending on your application. The can is basically part one. The second part is your light and reflector assembly. There’s a ton of different options on this front and can let you do some pretty cool things. The first question in cans is New Construction or Renovation design? New Construction cans come with sliding tracks that allow you to nail them directly into your ceiling joists. Their installed in unfinished spaces and wired up before the drywallers come in. Renovation cans are designed to be installed in holes you cut in your existing ceiling. You cut a hole the size of the can. Pull your wire through the hole. Then wire the can up outside the ceiling, and stuff the hole unit up inside the space. Little locking clips then hold it in place by clamping above the ceiling. Your project will dictate which one of these designs you should choose. For us, we actually got to use both. In the space we gutted and reframed, we put new construction cans in. In the kitchen, we put renovations cans in the existing ceiling. I think my preference is for new construction. It’s cleaner and doesn’t involve fishing wire.
When pulling wire in finished work, you’ll often use something called Fish Tape. Fish tape is a flexible metal wire that’s flat (like a thin tape). It’s ridged enough to push through tight openings. Once you get it to the other side, you tape the wire you’re trying to pull to it with electrical tape or whatever. Then you can pull the line from one end while pushing it through from the other. Wire, especially as it gets thicker, is really difficult to get around corners or through ackward areas so you really want to be able to push and pull at the same time. This process is kind of a pain in the ass and I kind of suck at it. But there’s not much choice for running electrical in finished space.
Back to the cans. The second thing you need to consider is insulation approved or not. Essentially, IR-rated cans (sometimes called airtight) are designed to be placed in spaces that are finished with insulation right up against the can. Think ceilings where the roof is right above your ceiling. These cans are constructed to stem the heat generated by the light bulb from going up into the space around the can and potentially causing a fire. Non-IR can can be installed in spaces where they won’t be touching anything besides the ceiling. If you don’t need insulation ready cans, then there’s not a lot of reason to use them. This is doubly true as lighting moves towards LED applications. LEDs produce far less heat than traditional incandescent lamps (they also consume far less energy).
Lastly, you need to decide on the size and number of cans you’re installing. The first two questions are kind of easy. You just consider your application and pick what you need. This question requires more finesse. Over the counter cans come in three basic sizes: 6″, 5″, and 4″. There of course, are special order products to fit most applications. We decided on using 6″ and 4″ cans. The large ones are for general lighting in halls and rooms. The small ones are for lighting over the breakfast bar. I ultimately installed three lights in the hall: 2 cans and 1 fixture hook up (to be decided later), and 7 in the kitchen plus 3 in the bar. I know there are programs and lighting simulations you can do to figure out appropriate amount and placement for your lights. I kind of winged it. The rule of thumb is to use the height as the diameter of the light cast. So, if you have 8′ ceilings, then you’ll have a light pattern 8′ across. I used graph paper and circle cut outs to try and figure out how many and roughly the best way to put in the lights. Then from that rough design, you have to fudge the actual install due to ceiling joists and other things you might find in the way. I also replaced the existing light fixture with a can in order to not have to try and patch the hole it left. In the end, I suspect an interior designer would notice how unpolished things are, but hopefully it’ll match the rest of our crookie house.
I feel I must point out something here. Em is a lighting engineer. Her job involves the design and testing of light bulbs. The proper term for what I garishly refer to as a light bulb is a lamp. The thing the lamp goes into is a fixture (or sometimes a system). The fixture contains the ballast. It’s an electrical component that converts A/C electricity into D/C and properly feeds it to power the lamp. So pretend I used these words properly in this post.
Wiring up the cans is a pretty straight forward task. The can has a metal box attached with a spring plate. Open it up and there will be three wires: white, black, and ground (non-sheathed copper wire). You’ll have 3 wires coming in from the cable you pulled. Just wire up the white to white, black to black, ect. When wiring multiple lights, just wire them all together. Things might get a tad trickier if your power is coming into the system in a funny way. For example, if your power is coming into the fixture first instead of the switch. I’ll get into switches in another post. There are two main brands of cans in Home Depot: Halo and Commercial Electric. Halo costs about 40% more but the construction is certainly worth the added cost. This is most noticeable in the wiring. Halo fixtures come with wired push connectors. You just pop open the plate, push your wires into some holes, and then close it up. It takes no time and it’s near impossible to screw up. Conversely, the CE fixtures use cheap, stranded wire that’s a pain to try and splice. If you ever have to make this call, I would encourage going Halo.