Lighting – Recessed lights, how to replace bulb

I have those exact cans and they are adjustable. Take out the bulb and remove the trim. Inside you will see two or three wing nuts. Loosen these and raise the level of base to the desired location. If the base is raised all the way up, then indeed your bulbs are too long for the trim you have selected.

Also note that every trim adds a different depth as well. Trims like eyeball sockets are much deeper and may solve your problem. I suspect yours is a flush mount one, and thus the distance to the base is shorter.

Get something that works with a standard medium-base floodlight bulb.

But when it comes to safety of heat dissipation and the load on the circuit and switch, don't assume the can will always have an efficient, low-heat LED or CFL. Build so the lighting is still safe to operate with nasty old EZ-Bake Edison bulbs.

IMHO, LEDs and CFLs are both already affordable, since they will pay off relatively quickly in energy savings. I haven't bought an incandescent bulb in years and I'll never go back to them.

One other thing to keep in mind: both LED and CFL bulbs are harder to come by in "dimmable" form, and having non-dimmable bulbs on a dimmer switch, even at full-blast, can result in annoying blinking and buzzing, and the dimmer switches made for LED and CFLs are pretty pricey for now. I recommend just putting in a normal light switch (again, watch that load!) and worry about any dimming features later.