The ranch house we bought a year ago is a tribute to 65-watt recessed/can lighting. There are nearly 40 of these fixtures throughout the house. I am at a loss for what to do with these fixtures. I would like something that would be more energy efficient and also considering costs.

Can you change to surface mounted fixtures or tracklights?  I'll bet air leakage and heat loss/gain are bigger problems for you than the incandescent lamps.  Fixing 40 of anything won't be cheap.

Bruce

About 17 of them are in a straight line down the hallway of our ranch house. What is the best way to cover up the hole where the current fixtures are?

It may be easier to overlay the corridor with 1/4' drywall. 

If not, it is a hole by hole process.  You can take a piece of 1x4 or a piece of metal stud about twice the size of the hole diameter to brace across the hole and fill in with a circle of drywall.  You may have to skim coat the whole ceiling to get a good finish or maybe use texture (if you like it) to help hide the patches.

Another possibility is to make some airtight drywall or sheetmetal boxes to put in the attic over the fixtures, anchor them with spray foam and insulate over them.  You could then use CF or LED lamps in place of incandescent.

In a wide and/or high corridor, you may think about sconces or suspended indirect lighting. 

I am a lousy drywall fiisher.  I am happy to write a check if the area is bigger than 1 sheet of drywall.

Bruce

By code all outlets, fixtures and junction boxes cannot mearly be covered up they must remain accessable.
the easiest code legal solution would be to install CFL bulbs , which are now very reasonable

14-15W compact fluorescents come in a wide range of color temperatures & color rendering, and put out about the same luminosity of 65-75W R30s (or R40s). But as Bruce points out, unless they're gasketed air-tight insulation-contact type they represent a gia-NORMOUS hole in the ceiling- a huge heat/AC loss.

Covering & sealing them in boxes from the attic side is also labor intensive, and difficult to make truly air tight.

It may be less work to completely pull the fixtures & wiring, and light with linear fluorescents in either coves, valences, or cabinet-top uplighting for zero glare ambient @ roughly 2x the efficiency of self-ballasted CFLs. (Dimmable ballasts are recommended if you go hog wild with it.) With the fixtures gone, making the hole air-tight is a lot easier. Where some downlighting is called for, a mix of 40%/60% of down/up-lighting (lumens, not watts) keeps the glare from the downlighting in check and much more useful.

Halls can usally be done with T5 valances, which should be considered:

If it's replacing 17 can lights @ 65W per that's about a 1000W.

You can deliver the same amount of light with self ballasted CFLs for 250W ( but it'll be just as glary.)

In coves/valences you can get the same amount of light out of T5 linears for ~125W...

... but since it's all indirect light, you'd be able to SEE as well (or better!) than the all-downlight solution with about 75-100W (literally an order of magnitude drop in power!)

If you keep it under 100W of T5 you probably won't feel the need to dim 'em, but if you go nuts and make it one long continuous cove with 250W of T5 it'll likely be too bright. Dimmable ballasts & dimmers are pricey- it's better to design the light levels right and use fewer, more modestly priced non-dimmable fixtures.

Read up on lighting design- there's tons of good stuff online from the good folks at the Rensselaer Polytechnic Institute here:

http://www.lrc.rpi.edu/

Done right, you end up doing a lot more with a lot less (less money, less power consumption), and have VERY nice visual ambience to live in. Lighting can make/break a house from a livability POV.

After playing Jr. Lighting Designer for a year or so, I almost never turn on the pre-existing recessed downlighting (retrofitted with dimmable 15W CFLs) in my living/dining/kitchen/family-room since installing dimmable T8s in coves & cabinet tops. In the kitchen I went with non-dimmmable under-cabinet task lighting mounted on the ROOM edge of the cabinet (with the fixture directed toward the wall), which puts the light closer to the center of the counters, and the backscatter off the walls fills in any hand-shadowing on the work (and since you're NEVER staring directly into a lamp you see better.) I did a 2-lamp 4' dimmable T8 parabolic high-mounted over the sink (overkill, usually dimmmed to about 8-12 watts in, as opposed to 65W full-on.) A couple of tiny sconces fill in the shadows in a stairwell & alcove with 2W cold-cathode bulbs even 5W proved too glary in the stairwell!

Now if I turn on every light in the house (not including the basement) it adds up to barely 1000 Watts, but from the street the place is glowing so hard it looks like it's ready to explode! :-)

For reference:

Incandescent R30s have an efficiency of ~12 lumens/watt

Compact fluorescent drop-in replacements, 45-55 lumens/watt

Cree LR6 drop-in replacement (pricey but) 55 lumens/watt

Electronically ballasted T8 linear, 80-100 lumens/watt

Electronically ballasted T5 linear, 90-120 lumens/watt

You can get a heluva lot more out of T5s & T8s, with a bit of construction. It it's super-hard carpentry to fab up some up-lighting coves to drop cheap box-store T8 striplight fixtures in, and it looks like a million bucks when your done. And a single 4-footer is worth 4 can-lights of luminosity, at half the power of one incandescent.

If the layout is reasonable, you could conceivably replace 40 can lights with 8-10 linear fluorescents, which is arguably a more tractable project. But it'll involve rewiring and a lot of chin-scratching, maybe (as it was with me), some experimental mockups with linear fluorescent fixtures in 'em to really see what it'll look like before committing. It'll be maybe a couple , maybe three hundred in fixtures & lamps with a lot of sweat equity thrown in, but probably less sweat than boxing in and sealing 40 cans from above.

Or, just buy a coupla cases of 15W R30 CFLs on eBay for $100, pretend the air leaks aren't happening, and be done with it. :-) (We all have our project-limits.)

was my thought as well

Yep- it really depends on just how much of a makeover you're doing to the place.  If it'll be more than a year or so before you're ready to take on more serious renovation, payback on a surplus case of CFLs will be under 2 years even in 5cents/kwh country.  (It can pay back in under 3 months in my neighborhood.)

But if you're going to re-light the place, do it right.

The wintertime heat loss from 40 leaky cans is very significant in 5000+ heating degree day climates, and may contribute to attic moisture condensation, mold, and ice-damming issues, as well as a huge adder to the heating bill.  (Seriously, between $5-30 PER CAN in additional heating costs, in a Pennsylvania Housing Research Resource Center study:  http://www.pct.edu/wtc/docs/articles/BB0502-Air-Leakage-in-Recessed-Lights.pdf ) 

Other studies from 10+ years ago have shown that the infiltration rates while off may be in the sub 1- cubic foot per minute (cfm) range, but will hit on the order 25cfm with a 100W bulb on.  The infiltration rate drive is roughly linear, so a 15watter would cut that to around or under 5cfm, but still...  Whatever the loss/cost is, multiplied x 40 it's huge!

But retrofitting it into a foamed roof deck, unvented attic would take care of all that without having to touch the interior space, for a lot less work (but more money) than building & sealing 40 boxes over the fixtures as a DIY project.

It sounds like you have a relatively large amount of fixtures in your house. I have an 8,000 sq ft home in Arizona and I decided to replace all of my fixtures with LED lights. Although the price tag on LED's is a quite a bit more than traditional bulbs, I was able to recoup my investment in less than 1 year. You have to account for the federal tax incentives and local utility rebates. I never would have known except my friends works at a company here in my home state that provided me with the ROI analysis that sold me, lol. The lighting quality is fantastic, I definitely recommend checking out an LED option.

(if you were curious, the LED products I used were from Opto-Lighting Solutions, www.olsled.com)

Hope that helps.

They make foam installation tops for high hats now, so long as you can get access to the top of the fixture, they can be easily installed. Then replace the bulbs with Compact fluorescent light bulbs, I have several in the kitchen and love them. They do take a minute or so to come up to full light strength, but once they are warmed up, you can't tell the difference.

I wonder if you could just take a can of expanding foam and just spray it all over the top of the can, provided that it is IC rated. You might have to smear it around a bit with a scrap piece of wood. I am going to probably end up using a few cans in my next house, and I have seriously been considering this method. Of course I will be combining that with CFL bulbs so heat shouldn't be a big issue.

It kinda depends on the temperature rating of the foam, but I don't think 1 part polyurethane (even "fire rated") cuts it- maybe 2lb closed cell iso does, but I'd look it up. Even self-ballasted CFL bases can run well over 200F in can-fixtures, and even if it didn't catch on fire most foams will eventually cook out, get brittle & crack losing their insulating value when run above their rated temp.  IIRC urethanes crap out somewhere between 225-250F for operating temp, styrenes give up around 200F.  Iso can run hotter- fiber reinforced iso is still the most common insulation in glazed solar thermal panels, where the ability to withstand 250F stagnation temps are something of a design minimum. (Can't remember what the max operating temp is though.)