D&D 5E Armour house rules for a low-tech setting. Do these seriously break anything?

[Crimson Longinus]

Personally? I would just replace armor with fantasy armor. Plate mail is replaced by turtle or ankheg shell armor. Maybe throw in some quests to get that shell armor.

Lot simpler, you don't have to futz with math. But I would also want to limit some of the spells, locks don't really make sense and many of the weapons.

I guess my point is that I don't see a reason to make anything more than cosmetic changes to armor if you aren't also going to redo all the other systems.

EDIT: ninja'd by @DMMike it will also depend on level of technology you have.

My first draft was exactly what you suggest. But then I made this more involved version. It is required to make wearing no armour whatsoever more viable.

 

[Oofta]

My first draft was exactly what you suggest. But then I made this more involved version. It is required to make wearing no armour whatsoever more viable.

Yeah, I get it. It's just that it feels like you're now stomping on the whole barbarian/monk theme.

Another option would be a feat that improved unarmored PCs. That way there's an associated cost.

In any case, I'd probably want to play test it a bit, probably in a simplified session where you just run through a couple of encounters at different levels with your group.

 

[DND_Reborn]

@Crimson Longinus ,

I think your ideas in the OP will work fine. I have often thought creatures ACs should improve as they are higher level/CR, even without "armor" (and our table's house rule does this), but the 5E model has been to not improve AC as much and allow the increased Hit Points to carry the slack (as it were).

I don't know if it is anything you want to incorporate, but here it is:

PCs (leveled creatures) get an AC boost equal to half proficiency (round down). So, +1 at levels 1-8, then +2 at level 9-16, and +3 at 17th and higher.
CRs (NPCs/Monsters) get an AC boost of +1 per 5 full points of CR. So, CR 0-4, nothing, 5-9 = +1, 10-14 = +2, etc.

 

[Fanaelialae]

Characters who might prefer to use armour but are caught without it are in less severe disadvantage. And as 'light armour' is basically replaced with 'no armour' so this also means that for high dex medium armour users going without armour might be a valid option. Overall this reduces the amount armours worn and makes them less essential whilst not eliminating them completely.

How do you figure?

An unarmored cleric with an 18 Dex has an AC of 15 (+ half prof). Wearing composite armor increases that to 16 (+ half prof). I'll grant that it causes them to have disadvantage on stealth checks, but medium armor users aren't usually stealthers. +1 AC for disadvantage on stealth is a good trade for anyone who doesn't rely on stealth.

The unarmored AC is only better than medium armor if you have the unarmored defense class feature, or if your Dex is 20. As such, I don't think you'll see many characters who can wear medium armor choosing to go unarmored instead.

 

[Crimson Longinus]

How do you figure?

An unarmored cleric with an 18 Dex has an AC of 15 (+ half prof). Wearing composite armor increases that to 16 (+ half prof). I'll grant that it causes them to have disadvantage on stealth checks, but medium armor users aren't usually stealthers. +1 AC for disadvantage on stealth is a good trade for anyone who doesn't rely on stealth.

The unarmored AC is only better than medium armor if you have the unarmored defense class feature, or if your Dex is 20. As such, I don't think you'll see many characters who can wear medium armor choosing to go unarmored instead.

Cleric indeed probably wants to keep their armour. Ranger on the other hand might not. They are likely to have good Dex, so once their bonus is +4 they can match leather armour while unarmoured and might indeed do that to keep functioning stealth. And once they get to +5 they are sure to ditch the armour. Now if cleric for some reason would choose to focus on their Dex and/or wanted to be stealthy these reason would apply too, but that definitely is less likely.