Fireplace advice

I bought a 'bakkie load" of dry blue gum for R800 delivered and stacked. This load was a standard bakkie filled to the height of the load bed, no higher. I estimate the piece count at about 650 pieces.
Haha - exactly my point - one persons "bakkie" load of c. 600 piece, is another persons "Half load" :)
[literally there are sites that say 600 is half load, 1000 is full load]

That being said R800 for 650 pieces seems a very good price. Do you have an idea how much each "piece" weigh? I get the impression it's around 1kg, but can depend on the wood, right?
 
Well - my curiousity got the better of me:

In general it looks to me like Black Wattle is sold at similar prices / kg than blue gum, but from some very simple research it sounds like it should produce much more heat? So the best value in Cape Town generally seems to be black wattle; and in general it doesn't seem to be too useful to buy lots - but then a "bakkie" load or a "piece" is obviously open to debate!



I'm getting a median price of around R1/kWh for seasoned firewood (assuming a 70% efficient fireplace)
Sometimes it does seem to get down to around R0.60/kWh - and as high as R2/kWh.
It's almost impossible to get an accurate figure on this. The specific heat capacity of wood varies with density, moisture content and even grain direction. So even with the same species of tree these figures can differ widely base depending on age, growing conditions, drying and cut.
 
Edit: Just ordered a fireplace thermal fan too. Not sure if it will make any difference in a 2.6m ceiling height space of 35m2.
Does anyone have any experience with these or any opinions?
No experience with them yet - but trying to figure out how to sort out my 'insert' fireplace that seems designed to not let heat into the room - so will look at this kind of thing once I can get it open!

It's almost impossible to get an accurate figure on this. The specific heat capacity of wood varies with density, moisture content and even grain direction. So even with the same species of tree these figures can differ widely base depending on age, growing conditions, drying and cut.
^^ not impossible really, there are scientific papers about it. I think the main issue is moisture content, but that really should be part of the wood being seasoned firewood, rather than green/wet. There does seem to be consensus that dry hardwood is around 18-20MJ/KG, . Whether bluegum is 12ish* or 19ish, is part of the issue I'm seeing (and constantly updating).
The real-life 'system heat' will depend more on how much is going up the chimney / how well you're burning the fuel etc... but buying different wood won't impact that!

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(I put links in the google sheet - please feel free to update them!)

Yeh, that's right... 35 million BTU's per cord... why do yanks use the crazies systems!
"Eucalyptus Blue Gum produces 34.5 million BTUs of heat per cord."
 

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Haha - exactly my point - one persons "bakkie" load of c. 600 piece, is another persons "Half load" :)
[literally there are sites that say 600 is half load, 1000 is full load]

That being said R800 for 650 pieces seems a very good price. Do you have an idea how much each "piece" weigh? I get the impression it's around 1kg, but can depend on the wood, right?
Only way to tell would have been to weight it. Pity these kind of okes don't sell by the half ton or something..
Maybe I'll try black wattle next. Thanks for the digging.
 
Only way to tell would have been to weight it. Pity these kind of okes don't sell by the half ton or something..
Maybe I'll try black wattle next. Thanks for the digging.
Blue gum was the first batch of wood in used burned quite quickly. Black wattle is def my pref
 
Finished off last season’s supply so started unpacking and stacking this seasons, it won’t all fit but I like having the storage rack looking ‘neat and tidy’…

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I see a lot of relatively small pieces.

Are reasonably sized chunks just not available because when it comes to fireplaces that's where it's at.
 
I see a lot of relatively small pieces.

Are reasonably sized chunks just not available because when it comes to fireplaces that's where it's at.

Only top left are small pieces which I'll use to start the fire, then top right is a mix of medium to large 'whole' logs, the middle section is the larger pieces and cut logs with the bottom being the weird sized or shaped stuff. I still have a lot to unpack but space storage is limited so it will happen over the winter...
 
so the weekend we went away adn they had a close combustion fireplace

damn that thing hardly takes wood

we added like 3 small pieces and we were burning rooikrans and we added more wood every hour or so

with my open fireplace every 20-30 mins im refuelling

@AchmatK lucky uou have tons of space

i picked up nice black wattle from a guy few roads away R1.20 a piece

but still have to chop it down
 
“2000” pieces bluegum (2 bakkie loads) - R2500 delivered and stacked CPT.

First thoughts
- green’ish wood
- maybe more red gum than bluegum
- chunky pieces (love this for fireplace!)

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so the weekend we went away adn they had a close combustion fireplace

damn that thing hardly takes wood

we added like 3 small pieces and we were burning rooikrans and we added more wood every hour or so

with my open fireplace every 20-30 mins im refuelling

@AchmatK lucky uou have tons of space

i picked up nice black wattle from a guy few roads away R1.20 a piece

but still have to chop it down
Nice. But please next time, rooikrans is actually bad for closed combustion fireplaces.
 
Nice. But please next time, rooikrans is actually bad for closed combustion fireplaces.
Yep burns too hot - you can warp / crack cast iron.

Fine to probably mix at like 1 rooikraans, 2 wattle etc - but just rooikrans is too much.
 
On a side note as OP of this thread fire place going nicely still best upgrade done to the house in a while! Never disappoints in winter!
 
Well, I have a Morso multifuel '90's model (1515 or something). I've had fires in it that have had the top cover glowing a dull apple red and the stainless flue pipe glowing orange. Burns anything I throw at it - even anthracite. No problems.

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