View Full Version : Determining the Size Modifier for Structures

2012-07-23, 08:51 PM
Due to a game that I am DMing, I need a quick reference for the size modifiers for structures that can be magically created. A medium sized structure, IIRC, would be about 5 x 5 x 5, and a large structure, would be 10 x 10 x 10. But what, for instance, would be the size catorgory of a structure that is 5 x 5 x 20? Or perhaps 5 X 10 x 50? Is there a quick rule or chart for it?

2012-07-23, 09:17 PM
You can take the squares they occupy and compare that to the squares a creature occupies. That 5x5x20 structure could be treated as Large because it occupies 4 squares, just like a Large creature. The 5x10x50 could be Gargantuan or Colossal. Probably Colossal.

You can also go by Table 9-10 on page 166 of the Player's Handbook. It gives you a quick approximation. Most structures will be Huge or bigger. Exceptions would be made for outhouses.

2012-07-23, 09:56 PM
The DMG rates a 10x10 section of wall as a Huge target. Source. (http://www.d20srd.org/srd/wilderness.htm#wallsAndGates)

As a practical matter, do not worry. As inanimate objects, structures will have ACs of "Anything but natural 1".