I also find it quite annoying. I would like to reply to the guy who said, if you cant defend it, dont build. The problem with that is that when a player cannot be online during a raid, there is no way to defend it. You can build as many room as you want, all they need to troll is to blast a few doors at the bottom of your base and replace them with their own.
I've been raided while I was online, I could defend myself, they reached far deep inside the base and it was quite fun to defend... I lost, but I had satisfaction because I had done something to defend my base.
On other occasions, I've been logging on only to realize that my many hours work had been compromised by either someone intelligently building a stair to the top of my building (its possible even with pillars, and its ugly!) or sabotaging my doors making it impossible to come back in. What could I do to prevent that? Nothing, except building nothing at all... because I wasnt there to defend it. I sure was sleeping, but thief doesnt usualy go into your house when you are there, and if they do, there would be chance for you to wake up. This is definatly not realism we have because it's impossible.
I'm not asking for an unraidable house here, it wouldnt be fun. Im asking for a way to defend it, and a way to avoid exploiting building in a coward way.
Some people have suggested the game text you if someone trips a wire near your base, or in your base, or breaches a door/wall, or whatever. There has been some discussion of adding electricity and wiring so you could make closed circuit cameras to broadcast video to your cell phone. I think that will likely be available at some point.
However, when I'm at work-- I can't defend my base-- I'm totally helpless. It's in many ways that feeling of helplessness while logged out that drives me. Removing that is like taking away a bit of the game's soul-- it would seem more arcade-y and forgiving, and less visceral and immediate.
I agree its more fun to be able to defend yourself in a desperate firefight, but most prudent raiders will simply fall back and try again when you aren't around. You probe for an enemy's weakness, you try and find the door he enters through, when he logs on, what time of day he goes out for resources-- and then you hit him while he's gone. Why would you do otherwise?
I'm cool with all manner of booby traps, spike pits, false floors, tripwires, claymore mines, etc. I'm all for the ability to dig down into the ground (fallout shelters). I agree passive defensive measures need a buff (a substantial one).
However, I absolute disagree that the default building mechanic should enforce anti-griefing.