Knotty pine gives an entirely fresh appearance to the room. If one is planning to go for this option you have taken the right decision. You have two options either you remove the earlier coat or add a new panelling to the walls. Whatever may be the case it will prove to be expensive for you. The best thing is to hire professionals who can give the perfect result. To begin you need to remove the paint and then apply a primer to it. This is done to make the finish strong so that the paint does not come out.
There are varieties of primers so choose a high quality one. Use a nice brush and at the end give a touch up to fill all the left spaces. Use different and exclusive lights if you are using a dark shade or the room will appear dark. Even windows can be included and given a modish look along with the room.