Help! Mysterious home odor
We have a 1928 house that we moved into 5 years ago. For our first couple of years, there was no odor. We did a lot of renovating, including turning an upstairs bedroom into a master bathroom. For the past 2 years, whenever the weather warms up, there is an awful smell in the master bathroom. The smell has now begun to spread through the house.
The smell is kind of sickly sweet - it reminds me of how an outside trash can sometimes smells when you open the lid and there has been trash inside. We have had the plumbing checked and double-checked, and there is no problem with it. We had a pest control company in several times, and no live or dead animals were found, and our attic was sealed to prevent anything coming in. We checked the air vents for any animals - nothing. We still can't locate the source of the smell!
When I sniff around for where it is strongest, I feel like it is coming from the air vents, but others have told me that the vents are likely just circulating it, not causing it. The smell is strongest by far in hot weather, regardless of whether we use air conditioning. It is worst when the windows are closed. Based on other people's posts, I have checked for too-hot light fixtures and haven't found anything. Any ideas welcome! This is driving me absolutely nuts.