Floor cupping need expert advice
Ok black butt timber flooring laid about 6 months ago wide boards about 140mm room area is about 5m x3 m.The floor has been layed on 100x40 joists which are held in place by stirrups as there used to be an old slab there so some of the floor is on 100x 45 and other spots its on 20x 45 battens there is little room under the joist maybe 50mm or so and there is no venting under the floor plus it’s a open plan bedroom with a bathroom at one end behind a timber wall. The entire floor has been painted white so all the boards are sealed.
I look at the bedroom today and every board has cupped dramatically and two of the boards have pushed up 200mm yes 200mm overnight we haven’t had any big downpours and under the boards looked dry.
Whatdo yareckon