Guides
Every guide on the site, grouped by problem. Each one ranks the likely causes, separates dangerous situations from routine ones, and tells you when DIY stops.
Smells in the house
Gas, rotten eggs & sulfur
Burning & electrical
Sewage & drains
Interactive diagnostics
How these guides are written
Causes are ranked by how often they explain a problem in ordinary homes, using plumbing, HVAC, electrical, and building-science guidance. We label rankings as judgments rather than dressing them up as statistics. Where a public agency publishes guidance, such as the EPA on mold and humidity or the CPSC on carbon monoxide, we link it.
Safety comes first on every guide: anything that could be gas, fire, or electrical gets a separate "act now" block before the troubleshooting. We don't give medical advice.