mtrs wrote:My uncle used, more or less, the same sizes in his house. It was initialy good but expanded tremendously and left a lot of huge gaps!
Can anyone give advice on how to avoid this?
You mean shrunk?
If you don't have access to kiln for drying, then you have to store the narra flitches for about a year after the tree is cut (maybe longer if the flitches are thick). You need to arrange the flitches so that air can circulate freely, by stacking them with spacers (enhance air circulation), check out how lumber yard stack their lumber. This will dry it enough so that it will no longer shrink.
Huge gaps on solid wood flooring is due to using the wood "green", as it dries, wood shrink.