Holz Hausen Experiment - Results are IN!!

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Well g'day again all, from Down Under. Yes, it's been a while since I was here last, sorry about that, I have a 4 month old son to go with the 3 year old toddler now, which pretty much explains the last 4 months absence :)

I have been working on the Holz Hausen experiment, in between cricket matches, and had a few problems with the first HH collapsing, then the second one having a minor spill as well . . . however all is good and I have updated my blog here:

Holz Hausen Experiment

with the first and second HH stories.

The logging of weather info hasn't been interrupted, so when winter comes & I pull it apart, I will be able to weigh and test moisture content with my cheapie moisture meter, and post results along with degree days etc for others to analyse. Hope you've all been well!

HH1_collapse.jpg


HH2_with_grid_wire.jpg
 
Not HH related but seeing that you are from Australia I am curious if you are in the heat wave I have been reading about - or any where near the fires. (News always sensationalizes things so I figured I'd ask a 'regular' person for their report.)

If you have browsed on some of the threads you know that some parts of the US have been clobbered with cold and wet stuff this winter. Seems like there should be a happy medium somewhere. :roll:

Congrats on baby number 2. I know it is hard to believe but they will be grown up before you know it and you will wonder where the time went so quickly.
 
We've certainly been getting some stinking hot days here, 42, 43 degrees (over 100 in farenheit I think? ) and I've even played a 6 hour game of cricket in it, took me 2 days to recover :)

But some parts of Oz, mainly South Australia and parts of Victoria (where those shocking bushfires killed hundreds of people and burnt 1800 homes) have been getting over a week of 40+, peaking at 47 degrees and no humidity. Hence the bushfire ferocity and speed of spread, 50km in 30 minutes for one firestorm. I'm hundreds of km's away from the bushfire area but of course have been bombarded with media reports on the bushfires for 2 weeks.

There's quite a lot of calling for more controlled burn-off or preventative firing, as the Victorian bushfires were burning through untouched bush with over 40 tons of fuel per hectare (over 8 tons per hectare considered dangerous Down Under, double the fuel, fire intensity grows 4 times, so 40 tons = ~20 times more intense than an 8 ton per hectare fuel load - every 5 degree increase over 30 does the same, so combine 45+ degrees and 40 tons a hecatre fuel and strong winds and it was an absolute monster of a fire we've not seen the likes of) which will also mean it becomes easier for guys like me to remove trees from local national parks as thinning programs increase and permit restrictions relax.

Meanwhile, northern Oz has been flooding for weeks! It really is a "sunburnt country with droughts and flooding rains" (famous Oz poem mis-quote).
 
Congratulations on the new baby boy and it's good to hear that the family's OK.
 
Great to hear from you, I've been wondering how it's been going. Sounds like you've had an excused absence! ;-P

I've been watching my HH for awhile now, wondering how it's doing. It seemed like it shrunk a bit after the first few months, but maybe that's because some of my bark roof fell off and I could see the center pole.

I think it will be real interesting to see how the splits in the center do, without being exposed to any sun, and less wind.
 
PDC- the pile will shrink. One of the cool things is that if you stick a pole in the middle with a mark at 80% of the height of the fresh pile, then it's supposedly dry when the pile shrinks enough that you see the mark.

It does give one pause to think about wood shrinkage when calculating what you need for next year.
 
Happy Shrinkage! Is that what they say at the beginning of the "Seasoning Season"?

Yeah, I have a center pole and marked it at 80%. Not sure I'll see it before I start burning it, the HH is all oak and I completed it at the beginning of October. I'm going to try a HH with some red maple that I just got and see how that does for the end of next season.
 
i think grandpa got it right , there is no replacement for stacking single row along a fence . i think the HH are neat looking but only popular in europe becuase they dont have the available yard space like we do and they plan years ahead of time.seems pretty simple the more exposed area the better the seasoning.
ill be eager to follow your findings however .
 
Could just be me but I think stacking in a rectangular shape is more space efficient than stacking in a circular shape. Both of my properties have wood stacked along the property line, giving me more space.
 
Gee it's good to "see" you all again! Thanks for the welcome back :)

I agree that stacking in rows and exposing more wood to sun and rain should season it faster. The more I think about HH's, having built a couple, the more convinced I am that is for aesthetic and space efficiency reasons. Volume is volume, but given you can build the HH's 8 or even 10 foot tall it does mean more volume of wood in a smaller area of land, and for those that don't like woodpiles - no-one around here I'm sure but they may exist! - the HH is a good solution.

I agree about the comment that stacking it along say a fence preserves more useable yard area eg for backyard sport with the kids, but you can't get single rows or ricks 8 or 10 foot high (safely) without some propping, hence the advantage a HH has for volume stored per land area.

Maybe I should have just submitted the thesis to "Mythbusters" and saved myself an awful lot of trouble from the start! :) However, it would be good to figure it out, I've got another 50+ years of wood-burning in me, and the wood burning years left on this forum alone could amount to millions! So we may as well all utilise the best seasoning method possible.

Even with my fence wire around it, my latest HH is growing on me, I quite like the look.
 
My problem is I always build my stacks too high, and they get unstable. I have tried Eric's trick with the rope through the middle, with mixed results, I'm probably doing something wrong. One of the things I like about the HH I built is that it is ROCK SOLID. It ain't goin' nowhere, I can lean on it hard and it won't budge. With 2 little kids running around that's a good thing.
 
Apprentice_GM said:
Regarding previous comments:

2) If an HH does not accelerate seasoning then I wonder why so many throughout Europe, who have trouble seasoning wood due to cold and wet climates (certainly compared to Oz) continue to take the trouble to build them. I doubt so many enjoy the aesthetics and efficient storage benefits compared to the time spent building them over normal rows, I would suspect function (faster seasoning) plays a part.

There once was a newlywed couple who were preparing to have the wife's family over for Christmas. As they were preparing to put the ham in the oven, the wife cut the end of the ham off. Her husband, surprised at this asked her why. She responded that it made the ham taste better and that she had learned it from her mother. When the mother arrived, the husband asked her why she cut off the end of the ham. "because it tastes better when you cook it that way and that is the way my mother always did it."

Determined to learn this amazing secret of ham gastronomy, he went to the grandmother and asked her why she cut the end of the ham off before she cooked it. "Because my oven was too small to fit the whole ham in" she replied.
 
My response has absolutely no scientific value to add to this discussion...

My dad and I built a HH this past fall with 1.75 cords. Why? I was tired of stacking in rows and I have not seen one in the area. In the end, it looks cool, it is the talk of the neighborhood and we had a great time building it (drank a lot too). Yankee New England can use a little something different besides straight stone walls and woodstacks. We painted the mark on the top to see if we get the shrinkage (or maybe just settling). Eventually it will get dismantled and stacked since it is not realistic to take from it for burning. It's relatively tall and awkward to get at. Once the "roof" is taken off it needs covering anyway.
 
wendell said:
Apprentice_GM said:
Regarding previous comments:

2) If an HH does not accelerate seasoning then I wonder why so many throughout Europe, who have trouble seasoning wood due to cold and wet climates (certainly compared to Oz) continue to take the trouble to build them. I doubt so many enjoy the aesthetics and efficient storage benefits compared to the time spent building them over normal rows, I would suspect function (faster seasoning) plays a part.

There once was a newlywed couple who were preparing to have the wife's family over for Christmas. As they were preparing to put the ham in the oven, the wife cut the end of the ham off. Her husband, surprised at this asked her why. She responded that it made the ham taste better and that she had learned it from her mother. When the mother arrived, the husband asked her why she cut off the end of the ham. "because it tastes better when you cook it that way and that is the way my mother always did it."

Determined to learn this amazing secret of ham gastronomy, he went to the grandmother and asked her why she cut the end of the ham off before she cooked it. "Because my oven was too small to fit the whole ham in" she replied.

Yeah I like that story :) Although the way I heard it, the original question was met with the new wife's retort "Because my mother did it that way" in a tone that brooked no further questioning warranted. Which is why it was funny and rewarding when the new husband persisted with the questions upline. Which is why I've always been encouraged to keep questioning despite the usual way of doing things.

Having now built 2 HH's and thought through the issue more, mainly whilst building the HH, I believe all those Europeans ARE building them for aesthetics and land area storage gains and possibly tradition, over improved seasoning. I mean it was a Chimney Sweep, based in the US, who claimed it seasoned wood in 3 months versus 2 years, not me. Here is the link:
http://www.thechimneysweep.ca/6seasoningwood.html
and a quote from the page:
"Build a Holz Hausen to go from living tree to seasoned firewood in as little as three months"
*Edward J. Zurmuhlen, AKA "Otto Best, C. S. E." Chimney Sweep Extraordinaire he lives in Ballston Spa, New York. He is an Energy Conservation Specialist with the New York State Energy Office. His forte is renewable energy.

I just want some empirical evidence one way or the other. I suspect it's like one of those urban myths that gets passed around (that HH's season firewood faster), growing until disproven.

I import cricket bats, and love my cricket. Cricket bats are made from willow, the best ones made from English willow. The willow is cut into clefts, seasoned, then shaped into cricket bats. There is a strong incentive on the part of the willow growers and sellers to season better and faster, as the drier the cleft, the better the willow performs (more "ping" or rebound of the ball off the bat) for the same given weight. Sometimes they try and kiln dry the clefts, with mixed results. The best clefts come from natural seasoning over time, 2 or more years. And how do they stack the clefts to season them? Not in Holz Hausen or cylinder / pyramid structures but in stacks (usually 3 or 4 east-west with 3 or 4 north-south in alternating rows) as you would for an end stack to a rick. England has a damp cold climate and could benefit from HH improvements if they exist, and would certainly know about HH's for firewood. So I suspect this whole "Holz Hausens season wood faster than ricks" is a myth. I will let the science speak for itself, when I get to the results.

And now I wait . . .
 
So what were the results? Does HH dry better faster or not. Or did the study stop and get referred to Mythbusters?
 
Nope, it's still going - I'm Down Under so this is the second summer at the moment, it will be ~18 months including 2 summers when done. I will be pulling apart the HH and the ricks and stacking under cover on the porch in April / May, and when I do I will be weighing the pieces and splitting and testing with the moisture meter.

I will then report results, probably late May.

I have been collecting the weather information as outlined and plotting in Excel as well.

Hope it's worth it . . .
 
Welcome back Apprentice if that last link is your HH...Holy Cow! Always good to hear from you.

ps with all the poisonous critters down in Oz is keeping wood on the porch really a good idea with a new baby running around? I dunno...I think whatever you think, just say'en is all.
 
savageactor7 said:
if that last link is your HH...Holy Cow!
WOW! It looks like you took a belt sander to the ends to even it up. That's the most evenly aligned stacking I have ever seen. Better than any of my straight ricks. Better than Highbeam's. Almost a shame it take it apart.
 
savageactor7 said:
Welcome back Apprentice if that last link is your HH...Holy Cow!

LLigetfa said:
savageactor7 said:
if that last link is your HH...Holy Cow!
WOW! It looks like you took a belt sander to the ends to even it up. That's the most evenly aligned stacking I have ever seen. Better than any of my straight ricks. Better than Highbeam's. Almost a shame it take it apart.

Hey first, thanks for the cheery welcome - I have been intermittently popping in and out but not as regularly as I used to (strange what the addition of 2 kids does to your previously ordered and packed-schedule life isn't it! Wouldn't have it any other way though . . .)

I am really sorry to disappoint, but I didn't build that HH - merely found it online and used it - along with Highbeam's beautiful ricks - in my blog / article (btw I sought permission to use the pics - Highbeam was gracious as was the German poster from a HH site). My pathetic attempt can be found by clicking through to the article. I had to use fence wire to hold it together! Might give you a giggle though :)

savageactor7 said:
Always good to hear from you. With all the poisonous critters down in Oz is keeping wood on the porch really a good idea with a new baby running around? I dunno...I think whatever you think, just say'en is all.

I stack it on the porch and then bring it in and immediately chuck it in the fire - it doesn't sit inside. I always use gloves when handling the wood for that reason too. I once had a funnel web spider - just the deadliest spider in the world - crawling around inside when a neighbour dug a pool and disturbed it's burrow, which still gives me shivers when thinking about it, as I had a crawling baby at the time who of course would pick up anything and taste it! Needless to say that spider lasted 2 seconds once I saw it. Bound to have a few snakes in the bush nearby too. I might give a bit of thought to that this year.
 
OK the results are in!!!Finally the results of the Holz Hausen vs Ricks (standard wood rows) are in and there is a clear winner! Common sense has prevailed over ludicrous untested claims - and the winner is Standard Ricks!!

Click here for my article and experiment data, but a summary is:

* Standard Ricks are a standout winner in the seasoning stakes over a HH. Ricks started with an average of 52% MC and fell to an average of 25% MC for a 27% MC fall, compared to the HH which started with an average of 51% MC and fell to 32% MC (those percentages are rounded hence the apparent discrepancy - the excel spreadsheet has the exact figures) for a 20% MC fall, which means the ricks lost a further 7% MC than the HH over the 18 months / 2 summers seasoning - or lost a third more moisture than the Holz Hausen. This is a significant difference in my opinion.

* The claim that a Holz Hausen can accelerate seasoning of firewood, even accomplishing it in 3 months, is ludicrous. Wood seasons with sun and wind and the more exposure to sun and wind the faster it seasons, so it makes complete sense to me that ricks would enjoy a significant advantage over HH's.

* The wood inside a HH seasons more slowly than wood in the outside ring. Mine even had some type of fungus growing on it, which whilst it might be a new generation of pennicillin, still doesn't help the seasoning and shows how damp and humid the air was all the time inside the HH. Again, this makes sense as per the above points on seasoning.

* Of some surprise to me was that the difference between the 4 compass points on the HH in terms of seasoning benefits from direct sunshine, was minimal. 2% better for North over South (remember I'm Down Under) - I would have thought it was much greater, but that's what careful measurement and experimentation is about.

However, the main outcome I was seeking was a clear refutation or upholding of the Holz Hausen accelerated seasoning claims, and I certainly feel I got that in spades. Don't get me wrong, I quite like Holz Hausens and can see a place for them, when one requires high volume of firewood storage in a small footprint, and I can see why some regard them as much better aesthetically - although I quite like my long ricks of firewood seasoning against my fence. You would have to leave them for much longer to get the same seasoning results though.

Thanks to everyone for following my experiment and I hope it "busts the myth" about Holz Hausen's and their seasoning rates.
 
Thanks for your report! Good to know, and it makes sense. I am still building HH and stacking in single rows where I can, but more importantly trying to get ahead!
 
I always knew Ricks were good for something. Now if I could convince the wife... %-P Rick
 
I love the sound of bullshit splatting on the pavement.

Thanks for the test and update.
 
fossil said:
I always knew Ricks were good for something. Now if I could convince the wife... %-P Rick

I'm only comparing and commenting on Standard Ricks. Clearly, you are a Non Standard Rick :)

I would suspect you contribute to house-warming far greater than either Holz Hausens or Standard Ricks - feel free to show your wife my empirical evidence backing your claim though!! %-P
 
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