making texture atlas out of building blocks

hi

i wanted to make various types of building and keeping the draw call and texture space as low as possible

so i textured some planes as building blocks like this

and i put them on top or aside of each other to make building like this


so my question is , is it possible make a texture atlas from my building blocks to make all my buildings using only the texture atlas as texture so all my buildings will only make one draw call if yes then how? i already looked at texture atlas generator addon and i don’t know how it can solve my problem , it makes uv map for all meshes.