Safety first:Suspect natural gas, smoke, fire or an active CO alarm? Leave the area and follow local emergency guidance before troubleshooting. Gas / rotten eggsSmoke / burning
Whole-home smells

Whole-home smells odor troubleshooting

Start here when the odor is hard to localize or seems to move from room to room. These are focused diagnostic guides, not an exhaustive list of every possible defect or local code condition.