Is renovation a word?

Yes, renovation is a word, and a completely standard one. It appears in every major dictionary as a noun meaning the act of repairing and improving something, usually a building, so that it's in good condition again. It has been in English for centuries. Nothing slangy or invented about it.

The doubt usually comes from two places. First, the misspelling rennovation is all over the internet, and once you've seen a word spelled two ways you start to wonder whether either is real. It's one n, always. Second, the clipped forms reno and refurb are so common in property talk that the full word can start to sound like the odd one out, as if someone had stretched a casual word into a formal one. It's the other way round: renovation is the original, reno is the shortening.

You'll meet it constantly in property. Kitchen renovation, full renovation, under renovation, a renovation project. Contracts, mortgage offers and planning documents all use it, so it carries formal weight as well as everyday currency. Our own contracts say 'the renovation works' and no solicitor has ever queried it. Whether it means exactly the same thing as refurbishment is a different argument, but as a piece of English it's as legitimate as words get.