Accurate Firewood BTU Values | 100+ woods rated

[Nord]

99% of BTU ratings you see online of incorrect for firewood. I decided to see if I could come up with BTU values correct for firewood, it turned into more, a lot more.

Enough of a journey that I wrote a blog post on how I came up with the data in my firewood ratings tables. You can read the blog post here:

https://boisafeudunord.com/blog/how-i-built-my-firewood-btu-ratings/

The firewood rating tables holds data for over 100 trees, you can see it here:

https://boisafeudunord.com/pages/firewood-btu-ratings

Hope some of you find it useful!

 

[RichE23ACR]

This is great, thank you!
A major area of curiosity is the flaming burn temperature of different woods. It feels like white pine or spruce warms the house up faster than most hardwood. I like having some available when I get home from work to get the stove cranking from a bed of coals. Perhaps it's a placebo effect from the fast bright flames. I'm interested to know others experience.

PS At our place in Maine, I keep a stash of "swamp" alder for the same reason, it burns hot & quick.

 

[cuinrearview]

Wouldn't the weight of the wood co-incide more closely with heat value?

 

[Nord]

This is great, thank you!
A major area of curiosity is the flaming burn temperature of different woods. It feels like white pine or spruce warms the house up faster than most hardwood. I like having some available when I get home from work to get the stove cranking from a bed of coals. Perhaps it's a placebo effect from the fast bright flames. I'm interested to know others experience.

PS At our place in Maine, I keep a stash of "swamp" alder for the same reason, it burns hot & quick.

Many softwoods burn fast and hot, it is a good way to get the heat rolling quickly, hardwoods tend to take some time to buildup the heat.

Wouldn't the weight of the wood co-incide more closely with heat value?

It does, density and specific gravity both, after that moisture content determines BTU.

The tables have been down for work since Saturday as there was some formula and code which were off. As I was fixing I found what I think are better ways to handle calculations and also got my hands on some more good data. Ended up rebuilding most of the tables. I also rewrote the blog post explaining just how I built them, sources, methods, etc. Added a print button as well, it will print standard black on white.

It has been an interesting excercise!

 

[Woodwackr]

Very cool.
I wonder where Siberian Elm fits in the list. We have a lot of that around here.

 

[HumBurner]

The truth is that any numbers you come up with will never accurately represent any firewood specifically, as each tree is different based on site conditions and its life experiences.

Even two, same-species trees next to each other may have vastly different ring-densities/growth patterns and provide different BTUs in the end.

 

[guym3]

Thanks for this which is really useful. Nothing can be totally accurate but this is a good guide.
One tiny point. You describe "white birch" as downy birch in europe. Most of the birch growing and cut for firewood in UK and much of europe is Betula pendula or white birch (renamed silver birch by Alfred Lord Tennyson). But downy birch is Betula Pubescens. Both excellent firewood and I keep some in as they flare up quickly and resurrect a dying fire.

 

[Nord]

Very cool.
I wonder where Siberian Elm fits in the list. We have a lot of that around here.

I believe Siberian is a bit less dense than other elm, I'll add it.

The truth is that any numbers you come up with will never accurately represent any firewood specifically, as each tree is different based on site conditions and its life experiences.

Even two, same-species trees next to each other may have vastly different ring-densities/growth patterns and provide different BTUs in the end.

I agree 100%, one of my main goals was to be able to come up with reasonable BTU estimates based on the wood properties and known data that would allow good estimates across 100s of hardwoods and softwoods. We are burning it not building pianos out of it so I believe it is working pretty well and is close enough to allow people to make informed decisions on their BTU requirements in regards to firewood.

You could have a lab measure exact BTU of a species and try again in a new location, altitude, tree age, or even different time of year and it would most likely change.

Thanks for this which is really useful. Nothing can be totally accurate but this is a good guide.
One tiny point. You describe "white birch" as downy birch in europe. Most of the birch growing and cut for firewood in UK and much of europe is Betula pendula or white birch (renamed silver birch by Alfred Lord Tennyson). But downy birch is Betula Pubescens. Both excellent firewood and I keep some in as they flare up quickly and resurrect a dying fire.

I will look into this and get it changed, thanks!