Engineered hardwood is good for radiant heated floors. I've always heard that quarter sawn wood is a bit more stable than plain sawn, so it might help to give some piece of mind. I'd probably try to avoid woods like hickory, maple or extremely hard exotic woods. Many people use these with no issues over radiant heat, but they are a little less stable then woods like oak, walnut, cherry. My personal preference would be quarter sawn white oak. It has good stability, is easy to stain, looks great etc. I always recommend getting a thicker product when using engineered as it allows you the ability to refinish the floors multiple times in the future (4mm or greater wear layer). Hope this helps.

"Wood Options

Although all premium hardwood flooring reacts to RH in the air, some species and cuts tend to have a smaller degree of change. Boards that are narrower tend to shrink less for a given change in moisture content in comparison to wider boards. As an example, a 4-inch wide plank will shrink twice as much as a 2-inch board. Therefore, the size of the gap between the boards that are 4-inches will be twice as big as the gap between the 2-inch board. The more joints in a board, the more places gapping is distributed.

Some species of wood are more dimensionally stable than other species. For example, for a given change in moisture content, Hickory tends to shrink more than Red Oak would. Using a wood with a smaller dimensional change will decrease the amount of gapping during the winter. The U.S Forest Services publishes dimensional change for different species. Along the same line as dimensional stability, quarter-sawn wood flooring shrinks about half as much compared to flat-sawn flooring for the same amount of moisture. As a result, under the same moisture, quarter-sawn flooring will produce smaller gaps than flat-sawn flooring."

Quote from "Protecting Premium Hardwood Flooring" by Peachey Hardwood Flooring
http://www.peacheyhardwoodflooring.com/ ... he-winter/