# Zombie Science: How long does stuff burn?

I couldn’t find a list of burn times anywhere for stuff, so I decided to do some Zombie Science!

Edit: Fair warning, I floundered around this post, the results of which are probably not useful. Feel free to skip this post and move on to the next post.

I loaded up a new Evacuee in a new world and used debug to wish for some quick materials and a brazier. I record the time when I light the material, and then read a book until the game stops me because it is too dark to read. I will record my results below:

1 piece of paper: 8:04:48 am to 8:29:06 am. 24 minutes 18 seconds.
2 pieces of paper: 8:29:54 am to 8:48:06 am. 18 minutes 12 seconds.
3 pieces of paper: 8:48:54 am to 9:08:24 am. 19 minutes 30 seconds.

That’s… weird. Let’s see if that replicates:

1 piece of paper: 9:09:12 am to 9:29:24 am. 20 minutes 12 seconds.

It seems that there’s some random variable involved here, and I’m just getting lucky with one sheet. However, it seems clear that with paper, just like with other stuff, it doesn’t matter how much is in it.

Now let’s try a newspaper:

Newspaper lit 09:30:12, goes out 09:50:12, total 20 minutes.
Test 2:
Newspaper lit 09:51:06, goes out 09:11:18, total 20 minutes 12 seconds:

This doesn’t seem to offer much advantage over single sheets, but might be less random

Now let’s throw a book in there:

Big Book of First Aid lit 10:11:42, goes out 10:23:06 AM, Total 11 minutes 24 seconds.

That was… not what I’d expected. Apparently a book lasts much less time than a sheet of paper.

Now to test something else regarding paper: using a firewood source full of it.

1 sheet of paper on the brazier, 2 sheets in a firewood source pile next to it.

Lit 10:24:06 am, goes out 10:34:30. Total 10 minute 24 seconds.

That’s weird… I want to watch that in action.

Lit 10:36:30, at 10:45:24 it goes out. Total 8 minutes, 54 seconds.

Because I was waiting manually it didn’t automatically put new paper on the fire. But why is it taking less time now than it was earlier? Am I just getting unlucky?

There’s some wood ash in the brazier. What happens if I remove that?

New 1 piece of paper lit 10:46:18, goes out 10:56:30. 10 minutes 12 seconds.

And I just realized what’s confounding my results. I switched books midway through.

Reading books is not a good way of measuring this, as It looks like you finish the current chapter regardless of light level afterwards.

I’m going to go ahead and post this, and try again with crafting something instead.

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OK, take 2. Lets try something else. First, will disassembling rags work?

1 piece of paper:

Time lit: 10:58:24. I disassembled the whole rag from just that bit of light.

Lets try something else.

Sharpening rebars with a hammer will take quite a while. Let’s try one of those:

1 piece of paper:

lit: 12:06:12, goes out 12:15:00. Total 8 minutes 48 seconds.

Replicate: 1 piece of paper:

Lit: 12:25:48, Went out 12:35:00, total 9 minutes 12 seconds.

Much more consistent.

Now 2 pieces of paper:

Lit 12:36:18, goes out 12:45:00, total 8 minutes, 42 seconds.

Seems like no change, really.

Now papers in a firewood pile:

1 paper in brazier, 1 in firewood source:

lit 12:46:00, goes out 1:00:00 pm, total 14 minutes.

Trying again with 2 sheets in the source:

Lit 1:01:00, goes out 1:10:00, total 9 minutes.

From this I conclude that something is wrong with using items treated as ammunition like paper in a firewood source. This confirms my observations in my regular game.

I will continue in further posts.

Kinda figured paper wouldn’t be too great. I’m actually quite curious how wood is going to stack up.

Now some more conventional burning research:

Newspaper: Lit 1:10:48, goes out 1:20:00, burn time 9 minutes 12 seconds.

rag: lit: 1:20:48, goes out 1:35:48, burn time 14 minutes 12 seconds

Splintered wood: lit 1:36:12, goes out 2:05:00, burn time 28 minutes 48 seconds.

Empty matchbook: lit 2:05:48, goes out 2:20:00, burn time 14 minutes 12 seconds.

Heavy stick: Lit 2:20:30, goes out 3:45:00, burn time 1 hour, 24 minutes, 30 seconds.

Long stick: Lit 3:45:54, goes out 6:30:00. Burn time 2 hours, 44 minutes, 6 seconds.

Log: 6:30:12, goes out 5:25:00 am the next day, burn time 10 hours, 54 minutes, 48 seconds.

How about 2x4s and charcoal? I’m wondering if your previous hypothesis about “ammunition” type items being inefficient is correct with charcoal since one would think it’s an idea burning material.

I’m very surprised to see non-fuel items burning so long. I seem to remember a time when I could dump a pile of clothes or random trash items in the fire and it would burn out moments later.

Two by Four: Lit 05:41:42, goes out 7:47:24, total 2 hours, 5 minutes, 42 seconds.

Charcoal: Lit 07:50:12, goes out 8:05:00, burn time 14 minutes 48 seconds.

2 charcoals: Lit 8:05:30, goes out 08:15:00 burn time 9 minutes, 30 seconds.

1 charcoal in, 2 in the source: lit 08:15:26, goes out 8:25:00, burn time 9 minutes 34 seconds.

So yeah, charcoal doesn’t burn for long at all and seems to have the same issue.

And currently it looks like two by fours are significantly better than heavy sticks.

Now lets test how efficient using a firewood source is:

3 splintered wood in the source, 1 in the brazier

Lit: 8:25:30, goes out 9: 45:00, total burn time 1 hour, 19 minutes, 30 seconds.

That’s interesting, given that the 28 minute time for a single splintered wood, times 4, would give you an hour and 52 minutes. It seems that the firwood source may be cutting off about the last third of the burn time of any individual piece.

Logically this would make sense as presumably the character has to toss the fuel on while the fire is strong enough to consume it. It’s interesting that even just the brazier seems to increase burn times by a fair margin if I’m reading that right.

It’s been pointed out that different furniture may have an impact on burn time, so in the interest of further science, let it be tested!

Starting over with a new zombie scientist, as the previous one was desperate for food, water, and rest.

All tests will be done with Splintered wood:

Test 1: Rock Floor on bottom of Evac Shelter
Lit: 8:02:30, goes out 8:15:00. burn time 12 minutes 30 seconds.

Test 2: Brazier
Lit: 8:16:12, goes out 8:40:00. Burn time 23 minutes 48 seconds.

Test 3: Oven
Lit: 8:40:48, goes out 9:10:00, burn time 29 minutes 12 seconds.

Test 4: Wood stove.
Lit: 9:10:48, goes out 9:35:00, burn time 24 minutes 12 seconds.

Test 5: Stone Fireplace
Lit: 9:35:42, goes out 10:05:00, burn time 29 minutes 18 seconds.

This might need more rigor, but it suggests that the brazier and wood stove are in a lower tier than the stone fireplace or standard oven. That really makes no sense if it’s the case: lighting a fire at the bottom of your oven should at best function similarly to a brazier.

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The burn time mechanics have never made much sense to me… did firewood source get added while I was away? (~8 months/right after the switch from smf)

I guess this is related but I remember when using “x” to look at a fire the estimated time it would last was all over the place. Without leaving the view mode but just moving off of the square with the fire and then back the time would be drastically different, going from “over 10 hours” to “less than 2 hours” and I’m not super sure what’s going on there but I’m guessing the game engine doesn’t totally understand how burning things works.

Yep. You can place it with the construction menu, though it takes no materials and no time. Basically you will automatically put stuff there into your fire while crafting, apparently when the fuel is about 2/3rds used up. This was added to counteract the fact that crafting is now interrupted if you stop having adequate light.

Real code insight: whatever fuel item is converted to fire fuel, and it results in less than thirty minutes of burning time, resulting fire is prone to half-life, so it may die out in that period randomly. If time of burning is larger than 30 minutes that extra time is guaranteed. Feedback info from examining a fire is adjusted to that process. However it’s reliable only when fire eats all items in it, because they add to the burning length. It’s a nifty mechanic, but there are some internal discrepancies that should be removed, and the fire code is old and would need some care. This does not affect balance fortunately, but for example fire in a pit will behave differently then fire in brazier, as they are governed by different logic.

Another test occurred to me: efficiency of long sticks vs splintered wood.

Long sticks are pretty easy to get, and turning them into splintered wood is easy too, but is there an advantage to doing so? Let’s find out.

Starting out, I get four long sticks and cut two of them up with a pocket knife. This produces 18 splintered wood.

I put 17 of the splintered wood in the firewood source spot and 1 in the brazier, and start crafting.

Lit 10:12:06, goes out 3:00:00 PM, for a total of 4 hours, 47 minutes,

And with 1 long stick in the brazier and 1 stick in the pile.

Lit 3:00:42, goes out 8:55:00, for a total of 5 hours, 54 minutes, 18 seconds.

So long sticks are significantly more efficient than splintered wood, assuming that you need at least several hours of burn time.

I thought this was going to be about actually burning zombies and how efficient that was, or is it leading to that?

Tainted flesh burns up basically instantly. I’ve been tossing it all in the pit to avoid plague roaches.

Ignoring for the moment the more likely plausible code being borked…Is there a connection between how hot something gets to how fast it will burn?

If so, this maybe realistic. Hotter = burn faster right?