Wood is hygroscopic — it takes up and gives off moisture, and it changes size doing it. Everything difficult about a wood floor follows from that, including the fact that you should buy it a week or more before you fit it.
Solid and engineered wood. Enter the room and the coverage printed on the pack.
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Wood is hygroscopic: it takes up and gives off moisture, and it changes size doing it. That is why you buy it a little long, why it needs acclimatising, why it needs an expansion gap, and why it moves seasonally once it is down. None of that is a defect — it is the material working as intended, and a floor detailed to allow for it will do so quietly for decades.
10–15 mm at every wall and every fixed object, covered by beading or skirting. Solid wood needs more than engineered because it moves more. And do not fit before the wet trades are finished and dry: plastering, screeding and painting put a great deal of water into a house, and wood fitted before that has dried out will absorb it and then shrink for the rest of its life.
The fixing method follows the product and the subfloor — solid wood is usually secret-nailed or glued to a suitable subfloor, while engineered can often float on underlay, and floating a solid floor is not a substitution you can make freely. With underfloor heating there is a surface temperature limit, commonly around 27 °C, and the system must be commissioned and run through a heating cycle before the floor goes down. Buy a spare pack: wood darkens with light over time, so a later purchase will not match even from the same supplier.
10–15 mm at every wall and every fixed object, covered by beading or skirting. Solid wood needs more than engineered, because it moves more.
No. Plastering, screeding and painting put a great deal of water into a house. Wood fitted before that has dried out absorbs the moisture, then shrinks permanently once the building dries.
Because wood gives off moisture in dry air and takes it up in humid air. A solid wood floor shows slightly wider gaps in a dry winter and closes them in summer. That is the material working as intended, not a fault.
Often, but with conditions. There is a surface temperature limit, commonly around 27 degrees C, and the system must be commissioned and run through a full heating cycle before the floor goes down. Engineered board is generally the safer choice.