Igniting an object

jgsugden · Jun 8, 2019

There are a variety of spells and items that ignite flamable objects. There is not a huge amount of guidance on what this means. How have DMs ruled it?

Let's say a 1st level firebolt that deals 1 damage will not destroy a large flamable object in one shot - but it would ignite it per the description. When does it take more damage? How much?

A fire elemental that ignites something continues to deal 1d10 damage per round. Is that a standard that DMs use, or do DMs have different damage for different types of fire sources? Spilling oil on something deals 5 additional fire damage if they take fire damage - that is about the same....

Shiroiken · Jun 8, 2019

I would go with 5 damage per round, but really anything listed as flammable will just burn away areas, like the web spell does. So if you had a paper wall, 1 point of fire would ignite it, and begin to spread the destruction around it.

the Jester · Jun 8, 2019

I mostly handwave it and use it as an excuse to catch areas the pcs are fighting in on fire, adding to the drama. I also have area of effects damage objects and structures when the pcs use them; there's at least one big tower on the verge of collapse in a nearby ruined city due to their actions with the shatter spell.

Paul Farquhar · Jun 8, 2019

Produce Flame into a thatched roof can lead to the docks burning down.

But my character wasn't anywhere near at the time officer.

aco175 · Jun 8, 2019

Generally I do not have things catch fire. I kind of picture magical fire going off so fast or hot and not having time to catch things on fire. I do allow things like firebolt to be modified to light a fire or torch, sort of toning down the spell. This can be prestidigitation as well making a Bic lighter.

If the player wants the PC to catch something on fire I may let them, but this may have only come up a few times over the last 20 years.

jgsugden · Jun 8, 2019

Paul Farquhar said:
Produce Flame into a thatched roof can lead to the docks burning down.

But my character wasn't anywhere near at the time officer.

Produce flame does not damage objects or ignite flamable objects on fire under the RAW. So, you're innocent.

Maxperson · Jun 8, 2019

jgsugden said:
There are a variety of spells and items that ignite flamable objects. There is not a huge amount of guidance on what this means. How have DMs ruled it?

Let's say a 1st level firebolt that deals 1 damage will not destroy a large flamable object in one shot - but it would ignite it per the description. When does it take more damage? How much?

A fire elemental that ignites something continues to deal 1d10 damage per round. Is that a standard that DMs use, or do DMs have different damage for different types of fire sources? Spilling oil on something deals 5 additional fire damage if they take fire damage - that is about the same....

This is one of those rulings over rules moments. You're going to have to look at the situation. Is it a large ball of thin, super dry paper? It takes a lot of damage really fast. Is it a rock covered in some dry moss? It takes only a little and then goes out. Are you in a desert? A swamp? Circumstances will change how this should play out.

jgsugden · Jun 8, 2019

So how have DMs ruled it is the question? What 'ruling over rules' approach did you take if you took that approach?

What objects do you consider to be flammable enough that a firebolt will ignte it?

Paper?
A pile of cloth?
Wood furniture?
A dried up bush?
A living tree?

Ovinomancer · Jun 8, 2019

Flammable means can be easily set on fire. I use the match test -- if a lit match touches the object, does it catch fire? Not held onto, but touches. If so, the item catches fire. Oil is flammable. Paper is flammable. Thatch roofs are generally not flammable (despite what movies show -- people tend not to make their houses firetraps). Wooden doors are not flammable. Curtains may be flammable.

In general, unless whatever your considering is easily set on fire, it shouldn't ignite from these spells.

Now, onto your question about fire damage. I got with a d6 if there is a fire in the space. This is how much damage a square of burning oil does (or if you're doused in oil) so it's a decent judge of spread out fire damage. If it's a conflagration, though, where the entire space and those next to it are on fire, then I'd be more likely to treat those spaces as impassible or instant death (absent protections). You can't run through a roaring bonfire and live, for example. In between, for a major fire that isn't a roaring inferno, likely 2d6 plus a d6 for each adjacent space fully on fire.