First off I am pretty new at blender. Now to my question… I designed a building. Then to make texturing easier I selected the parts of the building I want to have the same texture and joined them (ctrl+j). Then I applied the texture. My problem is that the texture does not appear on all the objects joined. It only appears on some. The same happens with colour. When I try to change the colour, only certain objects are affected, the same ones that show the texture image. Exactly what happened? And most importantly, how to I apply the texture to everything? By the way most of the objects I created I made by extruding vertices, not reshaping squares.
P.S. HELP ME!!! This project is due very soon for school.