Yeah with a dynamic object you can use an alttexture specified in the editor and then use script commands to switch between the two.
What I do is have a single texture map with a grid of colours and use different sections of the map for different objects so almost all of my entities static or dynamic use the same single texture map, incredibly useful for keeping file sizes down,
So put the roof texture on the top of the image file, the interior textures on the bottom half, export as a single image then retexture using that map and voila, both the interior and exterior textures are in a single image that can be used static or dynamic
smoke em if you got em