I'm assuming you're refering to in-floor radiant heating? You're not limited in what type of flooring. What you are limited to is installation methods. Real wood flooring is typically nailed down, but you can't do that cuz you'll puncture the heating tubes. However, I've seen where hardwood is glued down for just this reason. I don't know if they used fasteners of any sort.
Laminate flooring comes in a wide varietey of material compositions and levels of quality. Some brands and styles look real plasticy, not something you'd want to use in a bedroom or any common living space. Others however, can look very realistic. Going one further, some are finished with real wood. Laminate flooring is not nailed down at all, but is termed 'floating floor', because it's not attached in any way.
In short, your only limitation is that you can't use anything which requires nails, as the nails will puncture the heating tubes. With this in mind, shop around and find what suits your fancy.
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