I visited last weekend (£15 entry). It's on three levels: you come in on level 2, with changing rooms, lockers relaxing room, showers (3), Sauna (2), steam room and, a good size Jacuzzi. Leading off level 2 is a stairs down to level 1 and the Play rooms. In addition, there is access to level 3 with spacious play rooms from the relaxation area.
The upstairs play rooms are the best I have seen in a London Bath House.
The venue is very clean throughout. The best attribute this venue has is the clientèle: friendly and not unapproachable - like most London saunas.
Staff are equally approachable and keep things ship shape.