TJ here to talk about something our friend Dave Weston at Confessions of a 40k Addict has brought to life for free - a 3d Building Template, scaled to 40k that will certainly block LOS and can be found and printed for free, well, for whatever it cost you for the supplies, haha. Here is a look at it in real life:
Alright, so you are already going to tell me that you can find a free building template online. Does your FLGS have an issue with terrain? Particularly the kind that blocks Line of Sight (that would be 99% of all FLGS's I have EVER been to)? Well, here is a little something you can make or let a store know about that might add a little Christmas Terrain Cheer to your home table or the tables at your store. I like it because you can cut it up and make a few ruins out of just one template or ... you can have a building in the 40k universe that hasn't been destroyed! I have read about that once or twice in the fluff, haha. I think Dave has made for us, out of the kindness of his heart, a really cool building that can actually be a building, a giant line of sight blocking peice of terrain or some fun scenery in any tabletop game.
SO, to see more of this building and to find a link to download the building (and likely more great free templates from Dave Weston, check out this post here. Also, be kind enough to let Dave know what you think!