Hi sifus, would appreciate your opinions on the wall leakage in the 2 bedrooms of my condo unit (1 room next to toilet, 1 room opposite toilet).

SEEKING VIEWS
1) What could be the cause of the wall leakage? I suspect the leakage is due to failed waterproofing of the bathroom floor, which leads to water seeping from bathroom into the bedrooms with laminated flooring. I didn't see any leakage on the walls with tile flooring (e.g., no leakage in kitchen, dining room, area outside bathroom).
2) Any suggestions for a reasonably-priced solution to waterproof the bathroom floor? Prefer non-hacking but a permanent solution (maybe epoxy?). If available, can also share the estimated price in Klang Valley area for a 30 sqft bathroom.
LAYOUT

The leakage is on the lower walls next to the room doors.
The leakage only appeared in the last 1 year, when unit was rented out to tenants.
Both bedrooms have laminated floor, some water damage on the laminated floor near the doors.
The rest are tiled floors (living room, dining room, toilet, area outside toilet).
So far no complaints from the unit below about any ceiling leakage.


PHOTOS








Thank you so much for your views! Much appreciated