Combining various AC-providing clothing and armor

Question

Are there any rules for combining different clothing/armor for providing AC? For example, can an adventurer wear full plate and bracers and get the AC bonus from both? Can an adventurer wear a Cloak of Protection over plate? Can an adventurer wear a helm or crown and also plate armor, or does the plate armor include a mandatory helmet and preclude any other headwear?

I understand that ultimately this is up to the DM and what makes sense, but I would appreciate if there were some rules I could use as a foundation for rulings.

Answer 1

Does Armor Stack?

In general, there are two notations for AC:

• The most common variety sets your AC to a fixed value, and looks something like this:

  AC = 11 + Dex Modifier (Padded armor)

  Your AC equals 10 + your Dexterity modifier + your Wisdom modifier (Monk Unarmored Defense class feature)

• Alternately, some items increase your existing AC, and look more like this:

  Wielding a shield increases your Armor Class by 2 (shield)

  ... You gain a +1 bonus to AC (Fighter Defense fighting style)

When calculating your AC, you get ONE item of the first kind, and as many of the second kind as you can justify (except where contradicted by rules for specific items, e.g. you can only use one shield).

So if you have a Dragon sorcerer/barbarian, in full plate, with an extra set of padded armor under it, you have to pick which of the four forms of AC you use (Draconic Resilience, Unarmored Defense, Plate armor, or Padded armor). They do not stack.

But if you strap on a shield, that will stack because it grants +2 AC instead of setting your AC to a value. You can even strap on a cloak of resistance for another +1 AC.

See also:

• Does the Sorcerer feature Draconic Resilience work with shields?

• Does natural armor stack with unarmored defense?

What can I wear with Plate?

The rules state that plate armor consists of the following:

A suit of plate includes gauntlets, heavy leather boots, a visored helmet, and thick layers of padding underneath the armor.

There are no rules for substituting one piece of armor for another (e.g. a helm for a crown).

With that said, it is typically traditional to allow replacement of peripheral items (such as gloves, helms, boots, and bracers).

Answer 2

Bracers of Defence (DMG Pg 156) While wearing these bracers, you gain a +2 bonus to AC if you are wearing no armor and using no shield.

Plate (PHB Pg 145) Plate consists of shaped, interlocking metal plates to cover the entire body. A suit of plate includes gauntlets, heavy leather boots, a visored helmet, and thick layers of padding underneath the armor.

So you cannot wear bracers with any form of armor.

Cloak of protection grants +1 AC without such a stipulation so it would stack with plate armor.

As for helms and plate at this point there are no rules regarding substituting one part for another so it will be DM's call whether you can take off the helm from a suit of plate +3 and replace it with a Helm of Teleportation for example.

Circlets and such are often accepted to be able to be worn under a helm.

Answer 3

Yes, there are rules for this. Armour does one of two things: it either tells you what your new AC is, or it gives you a +X AC bonus. When a piece of armour just tells you what your AC is, they are not additive. Only when an item gives a bonus to AC can it be added to the AC provided by other items.