The Mysterious Case of the Leaky Light Fixture

My wife and son recently commented that the spare bedroom was looking “very dim.” “Can you add more light or at least add stronger bulbs?” they asked.

When I went to investigate the single overhead light, I could see through the frosted glass that both bulbs were functioning – but one did appear to be somewhat dull. I’ve installed LEDs pretty much throughout the house – do LED’s even get “dull”?

Regardless, when I went to take down the fixture to look at the bulbs, I was a bit taken back by the fact that the cap nut was very slick as if covered in oil. As I got the nut and washer off a thin stream of liquid ran out of the bottom of the glass covering and onto the bed. Oops! When I looked down, I noticed there was a large stain already on the bed – presumably from the same liquid. Once I got all the covering off though, I couldn’t see where this might be coming from; there was no obvious flow from above.  How is it possible for my house to have a leaky light?

The bedroom has an attic separate from the rest of the house and shared with the garage, so I went up into the garage hatch to see what I could see. The electrical box over the fixture was covered in insulation and didn’t appear to have been disturbed in any way, so it didn’t seem to be coming from above.