Smoke Smell in My House (Where There's Smoke, There's Fire!)
I thought I would post my experience today because this website gave me some guidance and maybe saved a lot of money, hassle and even lives.
My girlfriend and I moved into an old house three days ago. When I came home from work today the whole house smelled faintly of smoke, but not the typical electrical fire smoke of burning plastic or metal. Rather, it smelled pleasant and woody, almost like mesquite. But there was no visible smoke and fire, just the smell of wood smoke. At first I thought maybe a neighbor was barbecuing, but I did not smell it outside. I searched the house high and low and found nothing.
When my girlfriend got home a few hours later, it still smelled of smoke and she noted it right away. We searched again, checking all of the obvious sources (furnace, water heater, etc.) and less obvious places (outlets, fixtures), but found nothing. It seemed maybe vaguely hazy--you could only see it shining a bean across a room--but no real smoke and no fire.
We tested the smoke detectors and found that they were working. We called our landlord to see if anything like this had happened in the past--no. We checked and checked again. We Googled things like "smoke smell in house" or "wood smoke smell in house" to see if anyone had a similar experience, hoping it was something benign.
We decided to call the fire department. Although we called the "non-emergency" line, the fire department treated it as a five-alarm fire--a ladder truck, a fire engine, three other fire department vehicles, and about 15 firefighters in full gear. They searched the house high and low, too, using infrared monitors and other detectors, but they found no hotspots. Finally, though, they found a light fixture in the unfinished basement that was not working. They unscrewed the cover on the fixture and the whole inside, backing, box and wires were blackened and singed. The mesquite smoke smell was the old wood beam that fixture was mounted to. It had not burned in a true sense, but it was blackened.
In the end, the reason we called the fire department was because we saw a post on this message board that said, no matter what, just call the fire department and have them check it out.
So, if you came here because your house smells like smoke and you cannot identify the cause, please call the fire department! You will be glad you did.