Discretionary ! However, if you buy the soil is very poor, but not guaranteed , so buy now, and then spread the floor a little better, because it is your life Well, of course , the point of doing a good job, right? In addition, basic wood flooring , no blistering , then there will be no coup , I think that will not soak the wood floor with water overnight, Cece can be uneven wooden floor in the end , right? ? ? ? I suggest you buy some good quality items such as: Fillinger , Nature , Power Dekor are good, of course, more expensive than average price point , I wish you good luck. .