Donate to Remove ads

Got a credit card? use our Credit Card & Finance Calculators

Thanks to johnstevens77,Bhoddhisatva,scotia,Anonymous,Cornytiv34, for Donating to support the site

Using compressed leaves for a log burner

Straight answers to factual questions
Forum rules
Direct questions and answers, this room is not for general discussion please
Redmires
Lemon Slice
Posts: 786
Joined: November 4th, 2016, 6:49 pm
Has thanked: 831 times
Been thanked: 436 times

Using compressed leaves for a log burner

#451

Postby Redmires » November 4th, 2016, 8:50 pm

Let's get this DAK board going with a real question.

I watched Countryfile last week and there was a feature on bracken being harvested, compressed into logs and sold for log burners. Apparently they burn very well. It got we wondering why autumn leaves have never been treated the same way. There has got to be thousands/millions of tons going free every year the world over. A quick google suggests it may be a minor interest but how come a huge industry has not grown out of it ? I would have thought that the calorific value of bracken wouldn't be that much different from dried leaves.

Meatyfool
Lemon Slice
Posts: 313
Joined: November 4th, 2016, 11:43 am
Has thanked: 2 times
Been thanked: 55 times

Re: Using compressed leaves for a log burner

#475

Postby Meatyfool » November 4th, 2016, 9:19 pm

Bracken being more fibrous is more likely to be workable.

Leaves take little time to turn to sludge if it is wet.

Just guessing.

Meatyfool..

88V8
Lemon Half
Posts: 5769
Joined: November 4th, 2016, 11:22 am
Has thanked: 4098 times
Been thanked: 2560 times

Re: Using compressed leaves for a log burner

#1603

Postby 88V8 » November 7th, 2016, 11:28 am

Leaves make superb leaf mould. They just need composting for two years, wetted, in a binliner if there is no dedicated leaf bin.
Why on earth would one wish to waste that nutrient by burning them?

Bracken is another matter. There's so much of it. A caveat; the autumn spores are thought to cause cancers of the digestive tract.

V8

brightncheerful
Lemon Quarter
Posts: 2209
Joined: November 4th, 2016, 4:00 pm
Has thanked: 424 times
Been thanked: 799 times

Re: Using compressed leaves for a log burner

#2277

Postby brightncheerful » November 8th, 2016, 4:24 pm

According to Brackenbburn's site - http://www.brackenburn.co.uk/faqs - "When the bracken dies the carcinogen dies with it. We only bring in the harvest strictly once the bracken is dead and brown."

I used to make logs out of paper mache, soaking newspapers for a couple of days, squeeze out all water, compress in log-maker then store in dry place until ready for use, about 3 months depending upon drying temperature. Gave up after a while, for the effort entailed for the output heat wasn't enough. also a pile of paper ash is not the same as wood ash.

I suspect the same could be said of leaves. The effort entailed in compressing/compacting leaves to remove as much air as possible could be disproportionate to the output heat. Also the leaf source could be an issue, dog and cat mess, for starters.

---

I watched this Countyrfile because I know two of the people in it that were talking about perry. Chatting with them a few days after the programme was broadcast, I'm told that that single variety perry isn't made. Perry is a low demand product generally. Also, my question about the pears being bruised when falling off the tree is that provided the pears are whisked off pronto for making into perry the bruising doesn't spoil the taste.

Redmires
Lemon Slice
Posts: 786
Joined: November 4th, 2016, 6:49 pm
Has thanked: 831 times
Been thanked: 436 times

Re: Using compressed leaves for a log burner

#2524

Postby Redmires » November 8th, 2016, 10:37 pm

Thanks all for your thoughts.

We move into a new property in a couple of weeks and it will be our first with a log burner. I'll have a lot of reading and experimenting to do over the winter.

ReformedCharacter
Lemon Quarter
Posts: 3120
Joined: November 4th, 2016, 11:12 am
Has thanked: 3591 times
Been thanked: 1509 times

Re: Using compressed leaves for a log burner

#3475

Postby ReformedCharacter » November 10th, 2016, 8:27 pm

We move into a new property in a couple of weeks and it will be our first with a log burner. I'll have a lot of reading and experimenting to do over the winter.


A few tips from someone who has been heating their house (almost) exclusively by log stove for 20 years, I assume you live in the UK:

Buy as many logs as you can store, buying them from one of these companies that delivers them by the crate is a very expensive way to buy them.

If you are starting out, then you will probably be obliged to burn in the Winter the logs you buy earlier in the year but seasoned logs are MUCH better. Odd as it may sound, the best way to season logs is to make a big pile (don't bother stacking them) and let them get as wet as possible until the next spring. When they are really wet, cover with an old tarp if you have one, to stop them drying out.

The following spring (I start in Feb) stack the logs so they have maximum exposure to air flow. Given some dry weather for a week or two, they will dry out really quickly. Two weeks may be enough. Then store your logs for next Winter. Logs dried this are really good and give a great heat output.

For example, if I take some logs delivered in April and store them in my greenhouse all Summer they will be fairly dry and will burn OK, but they won't be a patch on logs exposed to the elements over Winter and dried in as little as 2 or 3 weeks.

Covering a pile of otherwise exposed logs with a tarp will not keep them dry, however hard you try. Condensation and wet ground is the enemy.

If you don't already have a shed or somewhere else you can store your dry logs then that is a priority, you just need somewhere to keep the rain off. Nothing fancy needed.

Keep warm!

RC

redsturgeon
Lemon Half
Posts: 8912
Joined: November 4th, 2016, 9:06 am
Has thanked: 1309 times
Been thanked: 3667 times

Re: Using compressed leaves for a log burner

#3645

Postby redsturgeon » November 11th, 2016, 10:20 am

If you are starting out, then you will probably be obliged to burn in the Winter the logs you buy earlier in the year but seasoned logs are MUCH better. Odd as it may sound, the best way to season logs is to make a big pile (don't bother stacking them) and let them get as wet as possible until the next spring. When they are really wet, cover with an old tarp if you have one, to stop them drying out.

The following spring (I start in Feb) stack the logs so they have maximum exposure to air flow. Given some dry weather for a week or two, they will dry out really quickly. Two weeks may be enough.



I hesitate to question the advice given above by someone with 20 years of practical experience but it does run counter to all of the generally accepted advice on drying and seasoning wood for burning as well as my own experience.

Clearly what you are aiming for is the get the moisture content down to the best level for efficient combustion, say 15-20%. Kiln dried at about 10% is too dry for the best combustion but that percentage is not really obtainable by normal air drying in this country so over drying is not a practical issue.

The accepted wisdom is to stack the fresh cut logs loosely with a covering on top so that maximum air flow is achieved while the worst of the rain is kept off. After a year or so of this, the wood can be moved to the wood shed.

All this varies with the type of wood used, birch for instance drying out more quickly than oak or beech.

I am struggling to understand why you would want to keep the wood wet over winter and also two weeks for the wood to dry out thoroughly seems far too short.

As I say though, if this works for you then I would not try to argue against it.

John

ReformedCharacter
Lemon Quarter
Posts: 3120
Joined: November 4th, 2016, 11:12 am
Has thanked: 3591 times
Been thanked: 1509 times

Re: Using compressed leaves for a log burner

#3706

Postby ReformedCharacter » November 11th, 2016, 12:32 pm

I am struggling to understand why you would want to keep the wood wet over winter and also two weeks for the wood to dry out thoroughly seems far too short.


I'm not suggesting that the conventional way you describe is wrong, you can of course dry logs that way, especially if you have the space.

My comment derives from the experience of leaving surplus logs in a pile over Winter where they are exposed to all the rain that nature provides. It is my conviction that the logs that have become wettest and are beginning to show signs of rot subsequently dry out quickest and make the very best firewood. You may also find, it probably depends where you live, that relative humidity levels are often lower in the Spring than the Summer and can dry logs very quickly. I have a choice of firewood for my stove at the moment, logs that have been under cover for two years and never exposed to the rain and logs that were treated as I have described. The 'old rotters' are lighter and produce noticeably more heat, yet they went from soaking wet to dry in about 3 weeks during March this year. A dry cold snap in the Spring with Easterly winds is terrific for drying. Try it, you may be surprised.

RC

redsturgeon
Lemon Half
Posts: 8912
Joined: November 4th, 2016, 9:06 am
Has thanked: 1309 times
Been thanked: 3667 times

Re: Using compressed leaves for a log burner

#3861

Postby redsturgeon » November 11th, 2016, 4:53 pm

Hi RC,

As I say, I don't wish to question your experience.

I have a couple of questions for clarification though.

1. What type of wood?

2. Open fire or stove?

I will try your experiment I have several piles of wood of different types and ages at the moment

I have some 5 year old cherry which actually was treated pretty much as you describe before I got it. I burns pretty well but took longer to dry out than yours.

I have some 2 year old birch and beech that I have dried outside but covered on top. Half of the beech is now in a shed but the birch is still outside

I have some three month old sycamore that is outside covered...in four stacks of about 2 cubic metres . I will uncover one of those stacks and see what happens in a year's time.

John

ReformedCharacter
Lemon Quarter
Posts: 3120
Joined: November 4th, 2016, 11:12 am
Has thanked: 3591 times
Been thanked: 1509 times

Re: Using compressed leaves for a log burner

#3883

Postby ReformedCharacter » November 11th, 2016, 5:10 pm

1. What type of wood?

2. Open fire or stove?


I get mainly Sycamore, Birch and Oak. We used to have an open fire (quite large) and it took a wheelbarrow full (slight exaggeration) to get it going. Had a Woodwarm stove fitted about 10 years ago, it's an 8KW model. I don't get a lot of hardwood but I can certainly imagine that Cherry would take quite a long time to dry. You have quite a lot of wood there!

RC

redsturgeon
Lemon Half
Posts: 8912
Joined: November 4th, 2016, 9:06 am
Has thanked: 1309 times
Been thanked: 3667 times

Re: Using compressed leaves for a log burner

#3887

Postby redsturgeon » November 11th, 2016, 5:18 pm

You have quite a lot of wood there!


Yup...been doing a bit of thinning out around the house.

The sycamore especially was a real nuisance, about four metres from the house, 70 foot tall and overshadowing the patio. There was not one time of year that it was not shedding something. We tried to get it cut down 15 years ago but we live in a conservation area and the tree officer said no.

I got a bit smarter this time though and put the application in the end of July. The tree officer had not responded in the regulation six weeks, so down it came! Lots of firewood! I've not burned sycamore before though, how is it?

John

ReformedCharacter
Lemon Quarter
Posts: 3120
Joined: November 4th, 2016, 11:12 am
Has thanked: 3591 times
Been thanked: 1509 times

Re: Using compressed leaves for a log burner

#3890

Postby ReformedCharacter » November 11th, 2016, 5:23 pm

The majority of my wood is Sycamore although it's a bit of a mix, I didn't mention Beech in my list, I get some of that too. I like Sycamore for burning, in fact it's warming the house at the moment.

RC

ReformedCharacter
Lemon Quarter
Posts: 3120
Joined: November 4th, 2016, 11:12 am
Has thanked: 3591 times
Been thanked: 1509 times

Re: Using compressed leaves for a log burner

#3894

Postby ReformedCharacter » November 11th, 2016, 5:31 pm

I should have mentioned perhaps, that most of the logs I get are split and about a foot long, that obviously makes a big difference to the speed of drying. Unsplit pieces of branch always take longer to dry than split. I'd suggest if you want to try the 'get it wet' technique you try it using Sycamore which dries really quickly for me.

RC

88V8
Lemon Half
Posts: 5769
Joined: November 4th, 2016, 11:22 am
Has thanked: 4098 times
Been thanked: 2560 times

Re: Using compressed leaves for a log burner

#4138

Postby 88V8 » November 12th, 2016, 12:38 pm

We have two woodburners in our thatched cottage.
Our base heat is ye olde storage heaters.
We run the woodburners in the evening as a top-up.
Both are Clearview 500.
They take 15" logs.

Generally it's best to buy 15". They last longest. But it suits my storage in the woodshed and in the hearths to have a mix of 15" and 10".

I buy them cut to length. When they're delivered I chop them thinner, to a degree, because great thick lumps are hard to get going. I use a 9lb axe and some iron wedges. A log splitter might be nice but I don't have room.

We get through around 3 tons of wood a year.
I always buy seasoned, preferably in late summer when they still have a good supply. If one buys in January for instance they tend not to have much seasoned stuff left. Most of it's beech.

My woodshed is watertight but has very good ventilation.

Fairly hard work:
Chop it - one handling.
Stack it - another handling.
Carry it up to the house and stack it in the hearths - another handling.
Then into the stove - another handling.
Then the ashes, which can be useful in the garden if applied to the right plants at the right time, but that's for the Gardening Board.

In our previous house we had gas ch. Here, there is no gas.
Do enjoy the stoves but will I still want to be doing this when I'm 80.

V8

Redmires
Lemon Slice
Posts: 786
Joined: November 4th, 2016, 6:49 pm
Has thanked: 831 times
Been thanked: 436 times

Re: Using compressed leaves for a log burner

#4307

Postby Redmires » November 12th, 2016, 10:20 pm

I have a lot to learn, so I've ordered a book to get me started.
"Getting The Best From Your Woodburning Stove" - it seems to get decent reviews on amazon.

I've also ordered a shed today - that's me sorted then :)

FarmerTom
Posts: 34
Joined: November 4th, 2016, 11:59 am
Been thanked: 3 times

Re: Using compressed leaves for a log burner

#4557

Postby FarmerTom » November 13th, 2016, 7:01 pm

I'd certainly agree with buying in as much as you can stor (once you've decided woodburning is really for you).
I store three years' worth, 45 cubic metres (OK I have a barn) as the wood I buy as 'seasoned' usually isn't.

Beware also that 'kiln dried' means nothing, and that wood at 10% moisture content will absorb moisture from the air.

Maybe take a visit to the green living forum or arbtalk where there are dedicated woodburning forums.
- You'll find a nice guy called Farmer Tom on there.......

brightncheerful
Lemon Quarter
Posts: 2209
Joined: November 4th, 2016, 4:00 pm
Has thanked: 424 times
Been thanked: 799 times

Re: Using compressed leaves for a log burner

#4886

Postby brightncheerful » November 14th, 2016, 4:58 pm

I used to burn ash. Bought a ton of ash logs, cut to the size I wanted, delivered loose, from the manager of a local forest; (all above board.) Over the years the price has more than doubled (from £75 originally) (become a seller's market) and I think when last year's load has run out I'll buy bags of mixed logs as I need them.

The first year I got the logs, (delivered dumped on the driveway (fell off the back of a lorry!) then carried by hand one-by-one (a few at time) by yours truly into the back garden. I arranged the logs into a pile and covered with tarpaulin. For impending immediate use, I stored a few in the garage or shed. Topped up from the garden pile after using them. The longer the logs are stored out of the wet the drier they become and faster they burn.

I was advised to buy ash because it's best for heat and slow burning. Ash being in short supply according to the supplier, I then had to have mixed wood logs more recently, heat output and burning rate not a patch.

Depending upon the design of the log burner, you may need to lower the temperature of the room before lighting the kindling otherwise any down draught smoke from the chimney flue will suffocate the flame and eek out of the vents in the burner and fill the room with smoke. Having got the having of how to avoid that happening, I now open the windows before lighting the paper underneath the kindling, then after closing the log burner door open it a little to allow some more air to get in so that the smoke doesn't get a chance to pile up. Before finally closing the door. Once the flames bave taken hold, I close the main vent and use the small vent to control the flame rate. Sometimes it takes a few attempts to get things going.

Once the logs have started burning, I suggest which is the more important for you. Efficient use of the material or the sight of flames. I go for efficiency, make the burning rate as slow as possible but a friend also with a log burning stove likes to see lots of flames so he keeps the vents on maximum opening. consequently the burning rate is faster.

My only gripe about using mixed woods is that the burning rate is faster, also some woods crackle and spit. Suggest avoid wood that leaks any stickiness, as the smoke goes up the chimney it can leave sticky deposits on the side of the flue.

brightncheerful
Lemon Quarter
Posts: 2209
Joined: November 4th, 2016, 4:00 pm
Has thanked: 424 times
Been thanked: 799 times

Re: Using compressed leaves for a log burner

#5589

Postby brightncheerful » November 16th, 2016, 12:27 pm

The front cover of this week's Country Life magazine is 'Grate expectation: secrets of a perfect log fire'.

Might be worth a look?

(Mrs Bnc has the time to read CL, I rarely do, so you'll have to wait for her to read it before I can comment further :)

UncleIan
Lemon Slice
Posts: 954
Joined: November 4th, 2016, 3:35 pm
Has thanked: 616 times
Been thanked: 456 times

Re: Using compressed leaves for a log burner

#5692

Postby UncleIan » November 16th, 2016, 4:20 pm

This reminds me...

The Firewood Poem

Beechwood fires are bright and clear
If the logs are kept a year,
Chestnut's only good they say,
If for logs 'tis laid away.
Make a fire of Elder tree,
Death within your house will be;
But ash new or ash old,
Is fit for a queen with crown of gold

Birch and fir logs burn too fast
Blaze up bright and do not last,
it is by the Irish said
Hawthorn bakes the sweetest bread.
Elm wood burns like churchyard mould,
E'en the very flames are cold
But ash green or ash brown
Is fit for a queen with golden crown

Poplar gives a bitter smoke,
Fills your eyes and makes you choke,
Apple wood will scent your room
Pear wood smells like flowers in bloom
Oaken logs, if dry and old
keep away the winter's cold
But ash wet or ash dry
a king shall warm his slippers by.

The firewood poem was written by Celia Congreve,

woolly
Lemon Pip
Posts: 68
Joined: November 7th, 2016, 10:21 am
Has thanked: 19 times
Been thanked: 21 times

Re: Using compressed leaves for a log burner

#5898

Postby woolly » November 17th, 2016, 12:16 pm

brightncheerful wrote:My only gripe about using mixed woods is that the burning rate is faster, also some woods crackle and spit. Suggest avoid wood that leaks any stickiness, as the smoke goes up the chimney it can leave sticky deposits on the side of the flue.


Just to add my penn'orth, we've found that one of the benefits of a log burner over an open fire is that it will burn just about any wood effectively as long as it's DRY. I've not heard of the weathering split logs in the rain technique - will have to try it! Dunno about the leaves thing - they do wonders for soil fertility without being burned - and as for compressed bracken, if it can compete with other sources on price and effectiveness, then I'm willing to give it a go. But one of the attractions of a woodburner is the DIY-ness of it - you can burn almost any stuff you find lying around in it. I will second (or third) the opinion that ash/oak is best - puzzled that with all the ash dieback going on it is still in short supply...

Sycamore spits, as do many conifers, but the woodburner gobbles more or less anything up quite happily. Also old pallets, sawmill and woodworking offcuts (procured over the summer when our local mill has excesses piling up that they want to get rid of) and the thicker sticks and branches from gardening.

The downside to using pallets and odd waste bits of wood is that the ash is full of nails and possibly residues of any pressure treatment the wood has been subjected to. That said, plants still seem to thrive on it but I'd be wary putting such residues on anything intended for consumption.

We have a three-bay log store - one for this year, one for next, and one for the year after. I've just about settled into a regular three-year rotation, splitting the logs for two years' hence during the current winter (as the scandiwegians say, you get warm twice splitting your own logs).

A small chef's blowtorch is just the thing to get the fire going - we still use paper/card/kindling but it speeds the whole process up wonderfully and can also be used to direct a blast of hot air up a chimney on the very rare occasion it has undergone reverse air flow, so no more living rooms filling with smoke.

As for using woods that exude sticky residues - generally these are conifers, which the Scandinavians and others have been burning quite happily for centuries. However they treat the flue as an integral and vital part of the log burner, and if the wood is dry enough the fire will burn hot enough to consume any resinous condensates (the whole point of a woodburner is the hot air injection into the upper fire region, which increases efficiency by burning particulates and partially combusted gases in the smoke to release more heat and reduce pollution). Resin in the wood just adds to its heat output as far as I can tell.

Meanwhile a stainless steel liner extending the flue pipe all the way up an existing chimney (preferably with the remaining chimney void packed with vermiculite) to make the entire flue line a uniform diameter does wonders for combustion efficiency, and will eliminate nasty deposits building up in the chimney, facilitate cleaning, and prevent the situation where fast-moving hot fumes are suddenly vented into a much larger, cold chimney stack, where they slow down, build up, cool, and condense on the wall of the chimney. I've seen several botched burner installations where the owners thought they were saving money by sticking the metal flue pipe of the burner straight into an existing chimney - result: first dripping black condensate leaking all around the flue pipe, then large amounts of crud building up in the chimney, and eventually a chimney fire.

UncleIan - loved the firewood poem, one to pin on wall of wood lore in the wood store. The olden-days folk had such a succinct way of passing on useful knowledge!


Return to “Does anyone know?”

Who is online

Users browsing this forum: No registered users and 11 guests