very nice and effective, as usual Svenn

did I miss where You told what You used for the walls?
for all other Thunderchicken:
No intention to diminish Svenn's performance here, however there are quite a lot "period 1" HO railway kits that look pretty much industrial. None is "true-scaled" like Svenn's, but they are pretty big and some have big enough doors, and windows anyway. I own some myself, and You can see others displayed in the "Tsingtao" game.
Of course these are kits, but the lazy ones (like me sometimes) can shoot them pretty cheap on ebay, and with some luck they are even properly built and painted.
But be aware: railway building kits in HO vary a lot in scale, so You should be sure to get the bigger-scaled ones. I've seen quite a lot of them, so just ask.
I also have a retailer around the corner who sells them 2nd hand
