[3.5]Item HP controdicting numbers.

[Omegas]

I am finding discrepancies trying to determine the HP of items with contradictory numbers. There seems to be a missing factor.

Although they say mats have different HPs based on thickness I get why they made weapons and armor follow a generic set of HPs. It is also contradictory but it saves a lot of time when they dont specify the exact thickness of items.

The thing is some of the numbers dont match up. I will stick with just PHB examples but I have notices this in many books.

Stone has a hardness of 8 with 15 HP per inch. 15x12=180 Yet in table 9-11 a 1ft thick stone wall has an HP of 90. This represents half the HP based on material. At the same time Iron Door follows the thickness specification exactly. One could argue that masonry is weaker then solid stone but it is still make of stone and it is less then likely that the iron door is a solid sheet of 2 inch thick metal. If the door was solid you would not be able to damage it with less then magical weapons regardless of how strong you were.

So my Question is this "what is the extra factor they are using to calculate these off static HPs?"

It cant be surface area as they state that large items specify have independent zones and small items have half the normal HP, while large items have their HP doubled. By all rights a ten foot tall section of one foot thick wall should have at least 360HP per exposed 5 foot square. Then looking back at the Iron door you have at least a 3x6 door 2 inches thick and it's full HP represents the total surface area of the door.

Book references or erratas are appreciated. Thank you

[Slipperychicken]

Stone has a hardness of 8 with 15 HP per inch. 15x12=180 Yet in table 9-11 a 1ft thick stone wall has an HP of 90. This represents half the HP based on material.


Masonry is cut with loose-fitting stones, held together by mortar. It's not solid stone.

Unworked/Hewn Stone is what you're looking for. That's solid stone: no mortar, no cuts like Masonry would have.

Unworked 900 hp for 5 feet. For 1 foot, you get (900/5=180hp). Same as the value you calculated.

Hewn is 540 hp for 3 feet. For one foot, that's 540/3 = 180hp. Also the same (it's just unworked stone that someone hacked down to size, after all).

[NeoPhoenix0]

Given D&D technology level the iron door has to be solid unless it was made by magic.

Also it seems stated appropriately. The average human would take about 24 minutes, give or take depending on luck, to hack away at the iron door with a greataxe before it broke. The average human is also incapable of using raw strength to break the door.

[Omegas]

Given D&D technology level the iron door has to be solid unless it was made by magic.

Also it seems stated appropriately. The average human would take about 24 minutes, give or take depending on luck, to hack away at the iron door with a greataxe before it broke. The average human is also incapable of using raw strength to break the door.

Based on some of the intricacy of the doors in the DMG they have hollow metal doors with highly leveled gear and puzzle tech. A solid 2 inch metal door would fall under the situation where the DM should rule that non magical weapons have no effect on the door like cutting a rope with a club. The thin 1/2 inch axe head would shatter before the Bullet prof door would budge or even show a significant scratch.

[NeoPhoenix0]

Based on some of the intricacy of the doors in the DMG they have hollow metal doors with highly leveled gear and puzzle tech. A solid 2 inch metal door would fall under the situation where the DM should rule that non magical weapons have no effect on the door like cutting a rope with a club. The thin 1/2 inch axe head would shatter before the Bullet prof door would budge ore even show a significant scratch.

Those are the states for a 2 inch iron door. Not a 2 inch thick puzzle box of doom.

Also, as long as you are trying to play realism instead of RAW, the axe head would only shatter if both the axe head and door wear both very tempered. otherwise one, the other, or both would deform over time.

In D&D rules, weapons are indestructible when hitting things that don't say otherwise.

[Slipperychicken]

Based on some of the intricacy of the doors in the DMG they have hollow metal doors with highly leveled gear and puzzle tech. A solid 2 inch metal door would fall under the situation where the DM should rule that non magical weapons have no effect on the door like cutting a rope with a club. The thin 1/2 inch axe head would shatter before the Bullet prof door would budge or even show a significant scratch.

Iron Door has Hardness 10; almost no weapon attack from an ordinary person has the potential to even scratch the door.

18 Strength Superheroes who eat live dragons for breakfast and who can wrestle Grizzlies, on the other hand, can take one down, but only with a lot of work.