Why this site exists
Search for almost any indoor air or water problem and the first page of results is mostly companies that sell the solution. That is not automatically dishonest, but it produces a predictable distortion: every problem turns out to be solvable by the thing that page sells. A humidity problem becomes a dehumidifier problem, a taste problem becomes a whole-house filtration problem, and a musty smell becomes a duct-cleaning problem — when the actual fix is often a bath fan, a downspout or a dehumidistat setting.
We start one step earlier, at the measurement. What does a hygrometer, a water report, a radon kit or a CO2 meter actually say about this house, and what does that result call for? Sometimes the answer is a product. Often it is a change that costs nothing, and sometimes it is a contractor. We would rather tell you that than sell you a machine.
How we are funded
Reader-supported, through Amazon affiliate links on the equipment we recommend. We are paid the same regardless of which product you choose, we take no payment for placement or review, and no manufacturer sees a page before it publishes. If that ever changes, it will be disclosed here first.
Scope
Deliberately narrow: indoor air, water, humidity and mold. We do not cover furniture, lighting, ergonomics or general home-office gear. Staying narrow is what lets us go deep enough to be worth reading.
How the site is organised
Six sections. Four of them are problems: Air, Water, Humidity and Mold. One is the diagnostic layer that feeds all four, Testing, which is where most people should start. The last, Spaces, runs the other way: it takes one room, a basement, a crawl space, a nursery, a bathroom, and works through everything that goes wrong in it.
That second axis exists because problems arrive attached to a place. Nobody wakes up with a filtration question. They wake up because the basement smells, or the shower water leaves a film, or the baby's room feels stuffy. The room pages meet that, then hand off to the section pages for the mechanism.
What we will tell you not to buy
Several categories sold heavily to homeowners do less than the marketing implies, and we say so on the relevant pages. Ozone generators marketed as odour removers produce a lung irritant. Duct cleaning is sold routinely and is worth it in a narrow set of circumstances. A water softener does not make contaminated water safe, and a carbon filter does not soften hard water, though both are sold as general purpose water improvement. Consumer mold test kits that grow a petri dish tell you almost nothing actionable.
None of that means those products are frauds. It means they solve a narrower problem than the shelf copy suggests, and the reader deserves to know which problem before paying.
What we are not
We are not a lab, not a contractor, and not a medical resource. We do not inspect houses, we do not remediate mold, and we do not tell anyone whether their symptoms are caused by their building. Where a situation calls for a licensed professional, the page says so and describes what that professional should be doing, so you can judge the quote you get.
We also publish no performance number we did not obtain from a named source. Our methodology sets out how to tell a figure we cited from a figure anyone measured, which matters more in this category than in almost any other, because manufacturer claims here are unusually difficult for a reader to check.
Corrections
We fix errors and say what changed. If a figure on this site is wrong, or a recommendation reads as though it were bought rather than reasoned, tell us and include the source. Send us a correction.