You could take of the plasterboard - then you will see where it is actually connecting to the rest of the house/room.... and discover more about it. The catch is, that if it turns out to be required you will have to re plasterboard it again.
DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!