D&D 5E Ignite flammable objects

[Herzog]

Hi all!

Several spells that do fire damage mention that the spell will (or may) also 'ignite flammable objects'
I have been unable to find any reference to whether there is a chance they are ignited (and how to determine whether they are ignited or not) and/or what happens when flammable objects are 'ignited'.

Because I have ALSO been unable to find any discussions on the topic I am wondering whether:
-It is spelled out somewhere but I have been unable to find it.
-It does not have any game effect at all and this is somehow common knowledge.

If anyone knows how this should be resolved I would be most gratefull.
If possible, please refer me to any rules handling the subject or, if rules are lacking and you happen to know of a discussion, that would be most welcome as well.

Any rules/discussions on mundane fire starting (using a lighted torch, for instance) would also be welcomed.

(re-reading the above: no, I am not planning to play a pyromaniac character. It just happened to come up in a game session where I DM)

 

[Umbran]

Giving you specific lists and rules of lighting things you can light on fire is not really 5e's approach to things. "Rulings, not rules," and all that.

If you, the GM, think it is reasonable for stuff to light on fire, *poof*, it is on fire! The exact impact of that is also for the most part in the GM's hands, as it will reasonably vary from case to case.

 

[Joe Liker]

Of course, I'm sure you came to the boards hoping for advice in making those "rulings, not rules," so I'll be happy to tell you how I do it!

First and foremost, I would never allow the ignition of a creature's held, worn, or carried items. That's right out, and many such spells explicitly disallow this in their descriptions.

In general, however, if the caster declares an intent to use a fire spell to light an unattended object on fire, I make it more or less automatic. If the spell requires an attack roll, I just have them roll to hit AC 10 unless the target is very, very tiny. Environmental conditions such as cover and concealment apply.

Attacking unattended magical items might be slightly more difficult. Most of them are not flammable, however, so this isn't usually an issue. But if someone wanted to burn up an unattended magic carpet, I guess I'd give it an actual AC and hit points and make them kill it with damage.

 

[Tormyr]

A few months ago one of the PCs bought a donkey and cart. As they used it to travel to Greyhawk, on the first day they were attacked by displacer beasts. The cart was represented by a 2"x3" cardboard square. He decided to use his new wall of fire spell against the beast that was right next to the cart. He lit his own cart on fire. Everyone continued fighting rather than put the fire out. by the end of it, everyone including the player who lit his own cart on fire was laughing as they watched the cart go up in flames.

 

[Bupp]

I can't tell you how many carts, wagons and ships my players have lost, destroyed or crashed over the years.

 

[Gilladian]

My thinking would be along these lines: sit down at your desk. Imagine that you have one of those automatic grill lighter thingies that holds some lighter fluid. Snap it on. Wave it over your desk. What would light on fire? I have a pile of loose papers that would definitely ignite. I also have a stack of hardback books in a rack/shelf thing. They probably wouldn't light immediately. Although there are 2-3 sheets of paper mixed in with them that might. The wooden desk top and shelves would singe badly, but not light up unless the pile of papers wasn't put out fairly easily.

So in game terms, I'd assume anything ON a desk or table would be ruined by burning hands, fireball, or similar brief, hot burst of flame. But anything that is IN the desk, or stacked up and somehow slightly protected by the shelves, would survive with only exterior damage. Leather books might blister, but not burn, etc...

Same with carpet on floors; it would be scorched, but not outright destroyed. Tapestries on walls, etc...

Things that are already dry, aged, and fragile, would be more badly damaged, possibly ruined. Magic items would be less hurt - the damage would be cosmetic, and would gradually disappear, because that's an established fact about magic items in my campaign world; they heal themselves of normal wear and tear.

Now, anything I WANTED destroyed, would be ruined. I mean, if I tell the PCs there are six lovely crystal potion bottles on a table in a wizard's lab, and they STILL fireball the room, well, they may only recover 3 of them afterwards. And anything I DONT want destroyed, will be protected. If those six potion bottles are critical to the plot (why would I do something that stupid?) then naturally, they were sheltered by the other equipment and didn't crack in the heat.

 

[RufusDaMan]

Burn buuuurn everything! I like magic powerful, more powerful than a normal blast of heat. Even a fire bolt will cause significant damage to items and surroundings. People shouldn't cast those things lightly. Since these spells were made to destroy, they do that very well. Casting fireball inside a house is usually a good way to set the whole town on fire.

 

[77IM]

Fire intense enough to cause hit point damage is pretty intense. I'd say an object takes 1d6 fire damage per round. On a 6, the fire spreads to another nearby object or space (like, if the floor is on fire). A creature moving through a fiery space or starting its turn there might be able to make a Dexterity saving throw for half damage.

I pulled these rules directly out of my butt, although similar rules have worked well for me in the past.

 

[MarkB]

A few months ago one of the PCs bought a donkey and cart. As they used it to travel to Greyhawk, on the first day they were attacked by displacer beasts. The cart was represented by a 2"x3" cardboard square. He decided to use his new wall of fire spell against the beast that was right next to the cart. He lit his own cart on fire. Everyone continued fighting rather than put the fire out. by the end of it, everyone including the player who lit his own cart on fire was laughing as they watched the cart go up in flames.

When my group encountered some ruffians who I described as lounging on an inn's front porch, either perched on barrels or leaning against post or the front of the wooden building, and things devolved from insults to combat, the wizard threw a Burning Hands before the ruffians had a chance to react.

It then took five minutes of persuasion before the wizard's player was prepared to concede that, yes, if he immolated a bunch of guys perching either on, against, or beneath a bunch of dry wooden timbers, it was likely to also set the building on fire.

 

[Anth]

I would use some sort of Item Saving Throw from earlier editions.
(and if you want to be really nasty, use the old rule that if a PC fail his save vs. a fire attack, all his items must save vs. fire or be destryed)
You have some guidelines for objects in DMG p246, but that's most for attacks, not for saves.
I would try to handle it with 5E-terms: vulnerable, resistant, immune: wood has a normal save, paper is vulnerable and thus has disadvantage on the save, wet wood is resistant and has advantage, stone is immune and don't need to save.