Natural Armor, Unarmored, Armor Worn, vs Ironskin Feat

[Mishapp]

Fifth Edition Feats, Feat Ironskin p16
Your Constitution score increases by +1.
You may add your Con bonus to AC when not wearing armor.

Will this stack with Natural Armor, and or Unarmored Barbarian ability Since neither of them are wearing armor.
We realize that will should not stack with worn armor.

The question for me is this,
I'm playing a Dragonforged Natural AC = 15 + Proficiency bonus, and I want to add the Ironskin Feat, since I'm not wearing armor.

thanks for the input.

[LordEntrails]

No. In 5E you don't stack or add multiple methods of calculating AC. You find the one equation that you are entitled to that gives you the best AC and use that one and ignore any other benefits etc.

[Mishapp]

So natural armor counts as not wearing armor correct?

If that is true why would the feat not work with natural armor.
So this would work with someone playing a barbarian correct?

[Nickademus]

If that is true why would the feat not work with natural armor.

The way the feat is worded, yes. This is why third-party content must be evaluated. They don't always follow the standards of WotC and can create these conflicts. The feat should have used the wording in the Barbarian Unarmored Defense feature to show it was a new choice for an AC calculation.

Natural armor is an AC calculation: Your Armor Class equals 10 + your Dexterity modifier + your natural armor bonus. Most creatures have an assumed +0 for natural armor so it better for them to wear armor.

[LordEntrails]

So yea, as the feat is written it could be interpreted to do what you want. It also could be used to build a character that is out of balance with others.

As Nickademus says, this 3rd party feat should have been better written so it doesn't do that. It's always up to the DM how to interpret and use such things. Hopefully the enjoyment of everyone at the table is taken into consideration when making such Rulings.

[Dax Doomslayer]

I'm not sure if this helps but this tweet from Jeremy Crawford may add insight...Armor Class Calculations don't stack

https://twitter.com/JeremyECrawford/status/787334304892268544