Hardwood floors over radiant is a beautiful thing & very comfortable. If installed correctly you can use virtually any type of hardwood on top of radiant, whether its solid, engineered, nailed down, nailed & glued down or floated. It is a misconception that radiant floor hurts hardwood, but really it is the relative humidity of the home & the hardwood that makes wood expand & contract. If you want to speak with a great hardwood company go to www.launstein.com they warranty all their wood products on top of radiant & have testing facilities of their own. Additionally, the company I work for, Warmboard, uses lower water temperatures than other systems. You can also nail hardwood directly to our product. Feel free to call or email if you have any questiosn 877-338-5493 cwebber@warmboard.com

I think you can have solid...just work with a narrower plank. The cut is also important. Some cuts are much more stable than others. Rift sawn lumber is more dimensionally stable (and more expensive) than other cuts. I would personally look for a narrow plank (more stable + cheaper installation costs) in a Rift Sawn presentation (most dimensionally stable + more expensive). I would guess you would end up spending about the same amount this way. Yet you get a more stable wood with fewer problems in a home without the added stability of humidity control. Of course you can move to engineered to avoid SOME of these concerns...but even engineered has limits re: humidity control (or lack there of).

It's a tough call to make because many of the pictures out there with wider planks look good. But they tend to be engineered wood - and honestly there's nothing wrong with that. They're a bit more stable dimensionally when it comes to cupping/curling so they're preferred if you want to go that way. Our builder spec'd a 2.5" red oak but we upgraded to a 4" white oak with simple stain. Compromise was that in areas with a herringbone pattern we mixed both to make it look more interesting. Here's what our 4" looks like.

You have a factory finished White Oak that has faded in sunlight ('brightened' is a nice way to put it). It will be almost impossible to match. It is *possible if you KNOW the manufacturer. There are many manufacturers who will continue to pump out a factory finished solid hardwood for years and years. But you need to know who did it and if they still do it. Now...you are welcome to drop in new, raw white oak (you must get the width and the cut and the GRADE correct) and then sand everything down. The dark look of the oak that was in the closet will sand out BEAUTIFULLY. It will be close to the colour of the rest of the floor once it has been sanded. Here's a quick question for you: How old are the original hardwoods? How old is the home?