What is the benefit if 1” ash layer in continuous burn?

[Easy Livin’ 3000]

I read and heard from several sources, including my wood stove manual, that I should leave at least 1” of ash on the floor of the firebox at all times.
Why?

More to the point, If I am doing continuous burns and the floor of the firebox never gets cold do I need to leave a blanket of ash? What is the actual benefit? I was thinking that not having the ash under the first layer of a new load of wood in a warm stove would be better because it would allow air circulation underneath the wood and aid the start.

What say you?

You ask a good question. Since there is already a layer off firebrick on the bottom of my stove, how much more insulation do I need?

So, in almost 40 years of burning, I've come up with this:. I start with no ash during the first load. Then I let it build up until it starts to take up too much space in the stove. If I have enough space in the ash bucket, I take it all out and start over. If the ash bucket fills up before all the ash is out, that's how much I leave. Somehow it seems to work out perfectly.

 

[Sean in the woods]

Do u have a link?

Sure.
https://www.woodlanddirect.com/ember-extractor/173085.html

 

[Sean in the woods]

You ask a good question. Since there is already a layer off firebrick on the bottom of my stove, how much more insulation do I need?

So, in almost 40 years of burning, I've come up with this:. I start with no ash during the first load. Then I let it build up until it starts to take up too much space in the stove. If I have enough space in the ash bucket, I take it all out and start over. If the ash bucket fills up before all the ash is out, that's how much I leave. Somehow it seems to work out perfectly.

Seems like a sound plan, especially since I too have firebrick lining the bottom.

 

[BigJ273]

Ouch. $51.

 

[SpaceBus]

That's a nice ash sifter. Someone on this forum made their own with expanded metal. I would do the same if I had some.

 

[CatfishHunter]

Coals are the most important ingredient to the equation with fresh wood, a layer of ash is optional but as others said helps the fire grow. In a continuous burn, I will occasionally pull out some ash from the sides and also a strip in the center. Airflow under the base of the fire is helpful.

 

[David.Ervin]

I think @CatfishHunter hit the mark - a layer of loose ash gives air a chance to get under the wood, while a fire right on the bricks on the bottom won't get that.

 

[jetsam]

I burn 24x7, and I've played with those coal shakers, all of which proved impractical in a hot stove. I even a couple years back went to scooping into a bucket, pouring the bucket through a deep fryer basket, then returning the coals to the stove.

Honestly, after the first time I accumulated 5 gallons of salvaged charcoal that way, I realized that I don't want charcoal for any purpose, and just started emptying the bucket into the ash pit.

In terms of scooping the stove, my stove burns front to back, so I tend to scoop the front out 10 times or more before I do a whole-stove scooping. I get a lot of ash out of the front and a lot of hot coal out of the back.

I rake everything before I scooping it to keep the big hot coals, but haven't found a practical coal seperator to use inside a hot stove yet, though I've made a few that didn't pan out.

 

[NickW]

For me, no deeper than 1". I feel like the ash chokes out the coals - really good draft when hot, loses it as it burns down. I use the coal shovel every 2-3 days. Slide everything to one side, scoop some up, shake the ash in the opposite front corner, charcoal/coals to the back corner. Repeat until all seperated. Scoop out the ash with a standard fireplace shovel if it's cold, into the ash drawer if not. Charcoal & coals turn to ash plenty fast on the reload - usually a smaller burn to re-establish a good coal bed.

 

[Easy Livin’ 3000]

For me, no deeper than 1". I feel like the ash chokes out the coals - really good draft when hot, loses it as it burns down. I use the coal shovel every 2-3 days. Slide everything to one side, scoop some up, shake the ash in the opposite front corner, charcoal/coals to the back corner. Repeat until all seperated. Scoop out the ash with a standard fireplace shovel if it's cold, into the ash drawer if not. Charcoal & coals turn to ash plenty fast on the reload - usually a smaller burn to re-establish a good coal bed.

Exactly my experience. I obsessed a little about trying to find an ash sifter the first year or two, but they really are completely unnecessary.

 

[Sean in the woods]

Exactly my experience. I obsessed a little about trying to find an ash sifter the first year or two, but they really are completely unnecessary.

But... TOOLS?!!

 

[SpaceBus]

I burn 24x7, and I've played with those coal shakers, all of which proved impractical in a hot stove. I even a couple years back went to scooping into a bucket, pouring the bucket through a deep fryer basket, then returning the coals to the stove.

Honestly, after the first time I accumulated 5 gallons of salvaged charcoal that way, I realized that I don't want charcoal for any purpose, and just started emptying the bucket into the ash pit.

In terms of scooping the stove, my stove burns front to back, so I tend to scoop the front out 10 times or more before I do a whole-stove scooping. I get a lot of ash out of the front and a lot of hot coal out of the back.

I rake everything before I scooping it to keep the big hot coals, but haven't found a practical coal seperator to use inside a hot stove yet, though I've made a few that didn't pan out.

The charcoal is great if you have gardens and chickens. Some folks like hardwood charcoal to cook or forge with as well.

 

[Grizzerbear]

I leave the ash in until it is taking up enough space that I can't fit enough firewood in for overnights. I probably have two inches in right now. If you load your stove e/w and your worried about it starving for air underneath just make the "tunnel of love" under center of wood with the ashes. They are quite handy for this. They also make your coals last exponentially longer. When I do empty it I let the stove go cold first. I usually leave a inch or so in and just toss the rest on the gardens or yard.

 

[Easy Livin’ 3000]

But... TOOLS?!!

I have an ash shovel and small all steel hoe that take up plenty of space by the stove. The hoe is sold at walmart intended to be a child's toy, but is really the perfect tool for working the ash down though the coals. It was $3, so I got two. The one lives in the attic and is used to hold up the light door we use to keep the heat from traveling up the stairs into the attic.

 

[Easy Livin’ 3000]

The charcoal is great if you have gardens and chickens. Some folks like hardwood charcoal to cook or forge with as well.

Do chickens like to eat charcoal? Is it good for them? I know they feed you activated carbon (charcoal) if you swallow certain poisons, but I think it's not good for you on a regular basis.

Or did you mean for grilling them?

 

[SpaceBus]

Do chickens like to eat charcoal? Is it good for them? I know they feed you activated carbon (charcoal) if you swallow certain poisons, but I think it's not good for you on a regular basis.

Or did you mean for grilling them?

Specifically I meant for the chickens to eat it, but you could definitely use it as cooking fuel instead. Charcoal keeps them clear of parasites and apparently they like it. I've read many folks even mix wood ash into commercial feed up to 1% by weight.

 

[Corey]

I think the ash layer can serve many purposes.

"Insulation" for the bottom of the stove...sure, but the heat is coming out one way or the other, so that might not be a great reason.

Insulation / protection for the firebrick itself... seems like that would have some benefit in keeping hot coals from directly contacting the brick. Would likely help prevent cracking of the firebrick.

Preventing an overzealous owner from shoveling / scraping the firebrick clean every time. Might help prevent some erosion of the firebricks. Given the way we attack the "Glass Cleaning" topic, I can only imagine what it would be like if manuals stated the bottom of the stove had to be clean after every use.

Provide an insulating layer for quicker start-ups / less emissions This may be a big key... if the firebrick is bare, then it can heat up with the fire, but that is taking heat which could be going into secondary combustion, or getting the secondaries up to temp earlier.

Overall, I'd suspect the 'inch of ash' probably started out to help protect firebrick (or even a bare metal bottom in really old stoves) and has continued on in EPA stoves for protection and as an insulating layer to promote faster start-ups and lower emissions.

 

[MoDoug]

I leave the ash in until it is taking up enough space that I can't fit enough firewood in for overnights. I probably have two inches in right now. If you load your stove e/w and your worried about it starving for air underneath just make the "tunnel of love" under center of wood with the ashes. They are quite handy for this. They also make your coals last exponentially longer. When I do empty it I let the stove go cold first. I usually leave a inch or so in and just toss the rest on the gardens or yard.

My stove has an air feed tube at the front middle of the stove, when I start cold, I load the wood in the bottom E/W and the piece of wood closest to the door I set on top of the air feed tube, so air can flow under the wood. After the fire is well established and I need to add wood, I use my poker to create the "tunnel of love" from the air feed tube to the back of the stove with the ashes.

 

[MoDoug]

The Native Americans used to carry a hot coal in a skin bag surrounded by ash when moving camps. The insulation of ash kept the coal going longer than when exposed to air.

We camped in Custer State Park in South Dakota, and they had a park employee doing demos and talking about the area. The natives in buffalo country would use the hollow of a buffalo horn to move fire from camp to camp. Native Americans were very resourceful.

 

[CatfishHunter]

They sell buffalo horns on Amazon for about $25 if you want to buy one. It might be your new (old) way of transporting a few coals from your inside fire to an sauna or firepit.

 

[SpaceBus]

They sell buffalo horns on Amazon for about $25 if you want to buy one. It might be your new (old) way of transporting a few coals from your inside fire to an sauna or firepit.

After reading some of the stuff on this thread I lit my cookstove this morning by carrying over some coals in a shovel. Tongs would also have worked, but maybe been a bit more tedious.