D&D 5E Barriers for detection spells -- how does it work for you/your group?

[merwins]

This is an inane question. I just wanted to establish that up front.

Detect Magic, and in fact many other spells, are stopped by various barriers.

Do you rule that the barriers must be continuous to qualify as a barrier? Or are you looking at the total amount of material through the range of the spell?

Also, when you "see" the aura, do you have to be able to see the object, or just "sense" it?

Consider the following scenario...

Spell:
Detect Magic. Range = 30 feet.
Barriers: 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt

Location:
5w x 10l foot hallway. Wooden door ahead of you

Situation A:
Stone walls are 1-foot thick to your left and right.
Wooden door is 4 inches thick.
Result: You can detect magic within 30 feet straight ahead of you. Left and right detection is blocked by the wall.

Situation B:
Stone walls are 6 inches thick to your left and right. Beyond the walls is a 6-inch gap, followed by 6 inch thick stone walls again, and then another hallway.
Wooden door is 4 inches thick.
Result: ??

Can you detect magic into the hallways to your left and right?
Can you determine the auras of any magic you detect?

 

[Warmaster Horus]

It's kind of strange because if the item is concealed behind a barrier it would not be visible. All you'd get is a vague sense that there is magic within range but not be able to see the aura identifying where the magic actually was and what school of magic it is, until you actually saw the item/creature the magic was cast on.

As a DM I'd rule you'd need a straight line of sight to the object, like vision, for detect magic barrier purposes. Any effective barriers that lay across LOS would block Detect Magic.

 

[Harzel]

I would rule that the barriers are cumulative, so in Situation B, detection does not extend into the adjacent hallways. Also that mixed combinations are also effective barriers, e.g., 6 inches of stone + 2 feet of dirt.

The spell description seems pretty clear that the creature or object must be visible in order to see the aura.

 

[merwins]

Ah, you're right. I missed the word "visible" in the spell description. Thanks.