How long should a wooden construct burn (and continue to take damage) until it burns out (and stops doing damage)

Question

My players encountered some wooden golems, which are vulnerable to fire damage. One of the players casts a Fire Bolt spell, the description of which says "A flammable object hit by this spell ignites if it isn't being worn or carried." So the next question is, after a wooden golem is hit twice with a fire bolt, how long should the thing continue to take damage due to being on fire?

I know the default answer is — whatever the DM wants it to be, but I'm taking the temperature of this community (pun intended). My first impulse is to say 1d6 rounds. Does anyone have a more compelling idea?

Answer 1

By the rules, it doesn't burn at all. The spell says it ignites objects but a Golem is a creature.

If you want to take inspiration from other mechanics that set things on fire, look at Alchemist Fire. It simply continues to burn until someone takes a DC 10 Dexterity check to put the fire out. The only reason a burning Golem would stop burning would be because it's either burnt up (which would be fatal) or because someone puts in the effort to douse the flames.

Putting it on the random timer mostly adds overhead, makes it something you can't really interact with, and also makes it potentially very painful for the golem (anywhere between X and 6 times X damage is a wide spread).

Answer 2

It shouldn't burn at all, it takes damage on hit

Fire Bolt only ignites objects:

A flammable object hit by this spell ignites if it isn't being worn or carried.

Since a construct is a creature, not an object, the quoted part doesn't apply to it. It takes damage on a hit and the spell doesn't have any effects other than that.

Answer 3

"Vulnerable" already covers the RAW flammability of a golem. Even if we choose to treat their body components as objects rather than a creature, they are certainly both "wearing" and "carrying" their own bodies. That ignition exclusion to worn an carried objects is obviously in place to prevent fire from breaking other game mechanics (making too many combats trivial, and frustrating players by too-easily depriving them of gear). But it also makes intuitive sense as an active creature can reasonably easily extinguish a flame that's just started and isn't being fed by an accelerant such as Alchemist Fire.

All of this supports the consensus of other answers that a wooden golem would not ignite at all. I'd take it further and posit that large masses of wood are not, in fact, particularly flammable. If I apply a blowtorch to a wooden bench I'll do much more damage to its substance than if it were metal or stone, which is reflected in the golem taking double damage from fire. But when I take the blowtorch away, the bench will not be ablaze. It takes a good deal of heat over a sustained time to induce a decently thick board or branch to truly and sustainably ignite. This is why bonfires have to be carefully constructed with tinder and kindling and a flow path for oxygen in and smoke out. Houses only burn because they're constructed in a way that coincidentally provides all those things.

So unless your wood golem is woven out of wicker and thin dry twigs, it won't ignite-- in game or out. I might have the lacquer on a jointed Pinocchio-style mannequin ignite mostly for visual flavor, but after a round or two when the lacquer had burned away my golem would look grotesque but be largely unharmed in any HP sense. An animated angry log would only take its double damage and some scorch marks.

Answer 4

Note that this is not a rules question

The OP is specifically asking for community opinions. Here are mine.

1. There is no such thing as a burning condition. There are monster abilities and items that state that a creature is burning and takes continuing damage. But firebolt isn't one of them. So from this perspective, it shouldn't take any damage even if it is on fire. So the duration doesn't really make sense.
2. Generally speaking, something being on fire is really more of a setting and flavor description. So from this perspective, it's cool to have the golems burn, so why not? But as this is flavor, they're not taking damage from being on fire. Maybe if a party was able to light them and then somehow be able to immobilize them and prevent the flames from being doused, then you could argue that eventually they're destroyed. But if the party can do that, they could probably have killed them more easily.
3. RAW a golem isn't an object, so isn't technically ignited by a firebolt. Maybe if the golem was made by an Animate Object spell one could argue that it's both a creature and an object, but even if it's on fire, it's not taking damage, as the spell doesn't say it does that.
4. The only way a DM could rule this is that it's improvised damage (DMG 249). This is usually a rule for monsters doing the damage, but a lenient DM could be persuaded to allow for this rule to be applied in this case, though it's far more likely that the fact that you did 2x damage with your fire damage due to vulnerability covers the extra damage, and the DM would tell you not to get too greedy with the effects of your cantrips.