Optimal length for firewood-non fishing, non political

[Weeds]

Hi guys, I'm about to order a bush cord of firewood. I've got a wood burning insert that measures 20 inches front to back. Am I ok with going with 18 inch pieces or would 16 be better for some reason? The house is reasonably new to us and although we've had numerous fires I've never had to order wood, just burned what the previous owner left us. I don't really know what lengths they were. You guys are normally a wealth of knowledge. Thanks

[misfish]

16" is the norm.

[dave524]

If it is a bush cord that 4 foot by 4 foot by 8 foot, so you are dealing with 4 foot/48 inch lengths, 16 X 3 equals 48 so 16 inch makes sense mathematically.

[misfish]

I quickly posted as I was busy, but,,,,,,,,,,,,,,,

 

I take from my pop here. He has trees he can cut down and split, but wants to keep what he has standing now. it will come down though if dead. So now he orders in logs. He cuts and splits and stacks a years or more worth. Says the saving is double if not triple, then ordering in cords.

[Old Ironmaker]

You will get better gas distribution resulting in better combustion at 16" rather than 18". The void space within the combustion chamber is greater. That's the theory. Would 2" make a huge difference in a small wood stove without doing a scientific study to prove it, I doubt it, in a 70,000 cubic foot Blast Furnace it makes a massive difference. The Brazilian Ironmaking Blast Furnaces burn Rain Forests of charcoal almost that large.

 

16" pieces would be easier to split but more to stack eventually. I wouldn't over think it.

[Weeds]

Thanks guys. The house is heated by a gas furnace so the fires are more for fun/ambience rather than a necessity. We live in peterborough and although it's a fairly large lot ordering anything larger than a bush cord is most likely out. The idea of ordering logs has a certain appeal but I have a hard enough time as it is now keeping up with things; can't seem to find an hour or two to even go fishing. Wife would kill me if I started playing lumberjack.

[misfish]

Thanks guys. The house is heated by a gas furnace so the fires are more for fun/ambience rather than a necessity. We live in peterborough and although it's a fairly large lot ordering anything larger than a bush cord is most likely out. The idea of ordering logs has a certain appeal but I have a hard enough time as it is now keeping up with things; can't seem to find an hour or two to even go fishing. Wife would kill me if I started playing lumberjack.

 

Well, you can buy by the bag then, at CTC.

 

Just amagine what she would think, after you split and pile after a day or so. Dear, you look so BUFFED. LMAO

[SirCranksalot]

Go with the 16". If it was avail as an option I'd prob buy it even shorter. I have a small wood stove but I would blister the paint on the walls if I kept it continually stuffed with wood. We also have a gas furnace, so the stove is for "entertainment". At night my wife watches TV and I look at the fire(or glance at it while I'm surfing). What I'm watching is --IMO-- more entertaining than what she's watching!

[Old Ironmaker]

If burning wood is for the ambience save you money and your back and turn on the "Fireplace" channel on the TV.

 

I was younger and know where you are coming from, enjoy. That TV wood burning channel doesn't come with that unmistaken smell of a wood fire. We no longer have the wood stove and I miss it. When a neighbour has their wood stove going I go outside in the freezing cold to smell it, my wife doesn't get it. I wonder if it is a deep seeded basic instinct from our Cave Man days, fire means warmth and cooked meat = success. Why is it Women don't get the same thrill Men do of fresh burnt meat? Grrrrrrrrrrrrrrrrrrrrrrrr.

[woodenboater]

Unless you burn a ton, a full cord is going to take some time to burn so it better be stacked off the ground with good air flow to keep it dry. Logs are good if wood is your primary heat source but it means you'll have to cut, split and stack and without a processor, it's a lot of work with saw and maul.

 

Do you really need a bush cord ? Also make sure you know what species you're getting. Most supply a mix of hardwoods (ash, maple, oak etc) but with some looking around, you can also get just birch.

[smitty55]

I buy tandem loads of logs myself and get 7-8 full cord for $1200. In fact I have a load of pure red oak coming after deer season. That will last me two years for sure, so figure the cost plus 20 bucks in fuel. Bottom line is I get my wood at half price, and I process it to my specs. Best exercise I get all year too, My stove is in the living room so I put in a smaller but quite efficient Napolean stove rated for 600-1500 sq.ft. and max 55000btu. The center portion of my bungalow is cathedral ceiling . With a 54" ceiling fan and two 20" floor fans blowing into the great room from each end I easily heat the whole ground floor which is 60ft long. With the furnace fan running full time and the hrv system come winter I can even keep the basement tolerable. That's without using my propane furnace at all except the odd time to keep the basement a boost.

 

What I'm getting at I guess here Weeds is that you may have a much better source of heat with that insert than you realize. I googled it and some of these inserts have real impressive specs and can heat large areas. You should really check yours out. This one for example, https://www.regency-fire.com/Products/Wood/Wood-Inserts/I1200 compares well with wood stoves. Same output as mine with a little smaller firebox even.

As to your original question, and like others have mentioned, combustion air is everything to an efficient burn. As you add wood into the available space there is less air available obviously and eventually you hit the trade off point where even with the draft wide open its harder to get big stuff going well, specially without a good solid coal bed and real dry wood. One thing for sure, as my ash bed builds up it hits a depth where my stove does not burn as well, two days max, and a 14' buck burns much better than 16" in my 18" firebox. In fact the manual recommends 12" as the optimal size, go figure, so that tells me what they are likely using to get those specs.

 

All stoves have their personalities and work best when treated a certain way I've found. Inserts won't be any different. With today's well sealed homes an open window can really help to get things going well too. You'll figure it out the more you use it. It's all about getting the stove and chimney hot.

 

There is absolutely nothing that compares to wood heat IMO, whether it's an outdoor fire, or standing in front a Findlay mama bear cook stove back in the day to thaw out after you finally came in from outside playing all day. My wood stove is the same now, I love the way the heat just soaks in you know... As do all guests who seem to like to park in front of it for a while..

 

Good luck with it all Weeds. I have a feeling the more you use that firebox the more you will appreciate it.

 

Cheers

[Old Ironmaker]

Good information Smitty. I hereby qualify you as a Solid Carbon Combustion Technician.

 

We have a 16 foot vaulted ceiling here. Do you have the ceiling fan blowing "down" or do you have it reversed to draught "up" ? I lost many a good nights sleep over it many years ago when I built the place and have since come to an opinion as to which is best. My opinion? it doesn't matter. As long as you get an air flow up or down it is a mute point. We have it blowing down as it takes less kinetic energy pushing it down than pulling air up. I think? Pick one.

[Weeds]

Thanks guys, you've been very generous with your time and knowledge, some great posts.

[woodenboater]

Interesting question about the ceiling fan OI. Either would work but I wonder if the updraft would give you a more diverse spread of heat/air flow vs pushing the air down which might lead to a less even distribution of warm air ?

 

Someone must have done studies on this lol

[SirCranksalot]

Unless you burn a ton, a full cord is going to take some time to burn so it better be stacked off the ground with good air flow to keep it dry. Logs are good if wood is your primary heat source but it means you'll have to cut, split and stack and without a processor, it's a lot of work with saw and maul.

 

Do you really need a bush cord ? Also make sure you know what species you're getting. Most supply a mix of hardwoods (ash, maple, oak etc) but with some looking around, you can also get just birch.

 

We burn about 1 1/2 bush cords a year and we have a gas furnace.

 

I rented a splitter to split 2-3 cords that I had scrounged.

 

I find the optimum mix is about 2/3 hardwood and 1/3 softwood. As others have said, you need to get the system hot quickly to avoid soot build-up in the chimney. I also use lots of kindling----usually scrap lumber scrounged from new houses being built somewhere in town.

 

It's bit of a learning process to operate the system----that's part of the fun!

[irishfield]

Hate to blow "smoke" into anyone's theory, but last week I finally made it to the top of my 40' fireplace chimneys to have a look down them.. with a 10 million candle power light. After 21 years... never been cleaned.. 4 bush cords a year +/- of burning nothing but Oak, maple and the odd birch in our fireplaces and we have ZERO build up and as I said they have never been cleaned. The very odd creosote " release log" throw in for chimney cleaning but that's it.

 

The secret... have a well designed fireplace and don't burn green wood or anything close to same. Soft wood has no place in a Southern fireplace, but no choice sometimes as we go further North. Dry your wood for 2 years minimum and keep it top covered while drying. Burn your fires hot with no fear that you're getting low on wood. DO NOT let a fire smolder while you try to get it started, or by starving an overnight fire for air hoping the "night logs" will last until morning. We're all of an age we're getting up at 4 am to pee, so get up and stoke the fire again or nudge the wife that you're cold and she can do it.

 

That said I did have chimney fires in our previous house with a wood stove, with the typical old air dampers on the front.. a "Johnson Converter". Almost burned my house down with the same wood "mythology" so a lot of the chimney cleanliness comes from proper unit design. Another important issue with lack of creosote is internal house insulated chimneys vs ones that immediately poke through the wall and are total outside in the elements. They cause immediate cooling of the exhausting smoke and coat in creosote. All my chimneys are boxed in and kept warm by the house, which is a 1000% + on keeping them clean.

 

As for the proper length to cut wood.. my great great great grandfather just limbed the tree and feed it in!

[pics]

16 is the standard.. mine is all different sizes depending on what I can scrounge. Tree cutters rarely cut for burning size so I have stuff from 10 to 18 inches.. I also search out hardwood pallets to cut up because they are mostly dry and heat like crazy.. I have a high efficiency insert so 16 inch wood works best... they can be finicky depending on the wind etc..

[Jds63]

I buy tandem loads of logs myself and get 7-8 full cord for $1200. In fact I have a load of pure red oak coming after deer season. That will last me two years for sure, so figure the cost plus 20 bucks in fuel. Bottom line is I get my wood at half price, and I process it to my specs. Best exercise I get all year too, My stove is in the living room so I put in a smaller but quite efficient Napolean stove rated for 600-1500 sq.ft. and max 55000btu. The center portion of my bungalow is cathedral ceiling . With a 54" ceiling fan and two 20" floor fans blowing into the great room from each end I easily heat the whole ground floor which is 60ft long. With the furnace fan running full time and the hrv system come winter I can even keep the basement tolerable. That's without using my propane furnace at all except the odd time to keep the basement a boost.

 

What I'm getting at I guess here Weeds is that you may have a much better source of heat with that insert than you realize. I googled it and some of these inserts have real impressive specs and can heat large areas. You should really check yours out. This one for example, https://www.regency-fire.com/Products/Wood/Wood-Inserts/I1200 compares well with wood stoves. Same output as mine with a little smaller firebox even.

As to your original question, and like others have mentioned, combustion air is everything to an efficient burn. As you add wood into the available space there is less air available obviously and eventually you hit the trade off point where even with the draft wide open its harder to get big stuff going well, specially without a good solid coal bed and real dry wood. One thing for sure, as my ash bed builds up it hits a depth where my stove does not burn as well, two days max, and a 14' buck burns much better than 16" in my 18" firebox. In fact the manual recommends 12" as the optimal size, go figure, so that tells me what they are likely using to get those specs.

 

All stoves have their personalities and work best when treated a certain way I've found. Inserts won't be any different. With today's well sealed homes an open window can really help to get things going well too. You'll figure it out the more you use it. It's all about getting the stove and chimney hot.

 

There is absolutely nothing that compares to wood heat IMO, whether it's an outdoor fire, or standing in front a Findlay mama bear cook stove back in the day to thaw out after you finally came in from outside playing all day. My wood stove is the same now, I love the way the heat just soaks in you know... As do all guests who seem to like to park in front of it for a while..

 

Good luck with it all Weeds. I have a feeling the more you use that firebox the more you will appreciate it.

 

Cheers

You have the same setup as I do at the cottage.

I installed a Napolean wood stove as well , pumps out the heat ... we also have a propane furnace.

I was told that code is you need an HRV , the installer told me today's construction is so air tight that's why the HRV is needed if you have a wood stove. I don't have an HRV , I burned last winter no issues... do I really need the HRV ? Lots of friends burn but don't have HRV's.

[irishfield]

Don't worry about an HRV pics. They can even cause a bigger problem and create a negative pressure in the house if not set up correctly and create a down draft in your cold chimneys and when your fire starts to go out they can create a carbon monoxide situation in your house. Why an external air input feed to the fireplace is essential in newer (20+ year now) homes. Even with same... I sometimes have to crack a basement window to get an updraft on fire start when it's colder than -25C.

 

Other causes of chimney downdraft are gas / oil fired furnaces and water heaters that don't have an external air source in HRV equipped homes.

Edited November 14, 2016 by irishfield

[DRIFTER_016]

406.4 millimeters is the correct length.

[Terry]

i think its 40.64 cm

[irishfield]

Unless you're feeding the first row at the camp.. and then it's 30.48 cm!

[Terry]

you cant make that thing burn, even with a blow torch if the bottom row isn't positioned right

[irishfield]

LOL..we've been at this toooooo long! I had to go back 8.5 years to find this picture!!!

[smitty55]

As to my ceiling fan, heat rises so it seemed like a no brainer to push the hot air down. Also, I never had an hrv unit before, but after the house was half rebuilt 4 years ago after a fire they had to put one in to be up to code. I've used it so far in the winter but not yet this year and after irishfield's points I might not bother anymore. I noticed what seemed to be a negative pressure issue the first winter with the new stove. I had them come back and adjust the unit which did help some, but I can't really say for sure if the unit is helping all that much. Plus I don't care what any engineer says, when I'm drawing in -25° air into the house it has to be heated. I totally understand how necessary they can be in some homes to prevent mold and provide air exchange. In my case I have no issues with humidity for the most part, I run the AC and a dehumidifier in the summer so my levels are never above 60% and in the winter I run a humidifier to try and keep levels up to 40%, but by midwinter I'm lucky to stay above 30.

 

Totally agree with your other points too irishfield. With a cathedral ceiling my stovepipe is all straight up indoors with one short 45. At least 80% of my burning over the years here has been red oak, which I love to use as it burns down to ash, with no charcoal like maple, which fills the firebox up quicker. I have never had creosote ever, all I ever get is a superfine ash which might add up to 2 cups worth every 2-3 years. I could probably never clean it and it would be fine, but I do it anyway. Like you said as well, try to mostly always burn a hot fire to get the best performance out of your stove, and specially when building a fresh bed. Airflow is everything. My door stays open a bit for a good five minutes at least as I start getting heat to the stove and chimney and work on the coal bed.

 

Funny you mention chimney fires. Here's one for the real old timers out there I figure. I was visiting a bunch of old buds at their hunt camp yesterday and Scotty mentions a name I hadn't heard for ages. Funny how that can suddenly trigger something you learned way back that makes perfect sense, but I've never heard of it anywhere else. So this real old farm gal still lived by herself in the old farmhouse after pa died, which was getting real rough. But she didn't want to leave. A good bud is renting another farm off her back then, so he tells me that chimney fires aren't uncommon, she's had a few. Pretty scary for an old gal on her own still. Well, Hellen Gillen wasn't scared. She had a coffee can full of powdered sulfur beside the stove. When there was a chimney fire she would throw a scoop or two on the fire and the burning sulfur would displace all the oxygen in the chimney and extinguish the fire. Old time country smarts there I tell ya... Anyone else ever heard of this?

 

Cheers