I have a Boral Silkwood floating floor over slab on ground. Looks great during winter, but come summer it rivals the big dipper at Lunar Park.
A bit too wavey !
Needless to say, whoever laid it did not leave any gaps for expansion. The main area is 11 m long by 5 m wide, with the boards aligned along the 5 m direction. The floor continues into other smaller spaces on three of the sides.
Any advice on retro-fitting gaps into this floor would be very welcomed.