Lagging in my house, specially doorways

Hello!
So, I have a huge problem with this bug and I’m wondering if it’s just the server I’m playing on or actually a known bug?
So basically what happens, is that I get huge FPS dropps when I enter my house. I noticed it specially happens when I open doors.

I’m playing on [EU]ACTIVE ADMINS|MAX LOOT|PVP , highly populated server and after asking, it seemed like I was the only one with the problem.

If it’s a known bug or anything, is there anything I can do to help at least reducing the dropps?

Thanks a lot for every answer!

[editline]20th December 2013[/editline]

Anyone? :confused: