ah, the pipes are easy... What you want do is a projection mapping for the UVs... pick an angle that covers the most surface... but you also want it to be flat, so a top view would be best.
Once you've created the UVs, select the edge loop that runs along the inside of the pipe (the bit that will be facing the building) and then split the UVs along the selected edge... It's the button in the UV texture editor... the one with he scissors on it.
Then simply select the UVs, and unfold them, in the UV texture editor: Tool> Smooth UV Tool. There will be two little buttons, one says 'unfold' the other 'smooth'. Use the unfold... now when I did this just now on my comp.... it unfolded it out really nicely... granted there may be a couple of UVs you might want to straighten up... but that's easy.
www.stevenegan-cgi.com
"Your weapons are no match for ours! People of Mars, surrender!"
"Um, this isn't Mars. This is Earth."
"Earth? Earth-with-nuclear-weapons Earth?"
"Yes."
[long pause] "Friend!!"