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Environment bill 2020


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2 hours ago, Woodworks said:

You got it. Some numbers for average humidity (RH) and temp for each month. The numbers are from a fairly fancy weather station we bought

 

September 14.1C     89%RH 

October       10.7C    93%RH

November     7.3C     93%RH

December    5.5C     91%RH

January         6.4C    91%RH

February       5.4C    91%RH

 

Then match each with the wood equilibrium tables or the link and you can see no air dried or kilned dried log exposed to our atmosphere can stay below 20% 

     

kosteus_en.png

What worries me about this chart is that woodworkers and joiners generally use moisture content referenced to the dry weight of wood, for burning we usually reference the wet weight of wood and I cannot see on this site which moisture content they are using.

 

So for instance if we have a mass of wood which consists of 20kg of water and 80kg of oven dry wood then a joiner might say that's 20/80=25% mc dry weight basis whereas I would say that's 20/100=20% mc wet weight basis.

 

Also there is a hysteresis so as a log regains moisture content at a given RH and temperature it tends to maintain a lower moisture content than the same wood being dried in the same conditions.

 

It is of course  in the ballpark of gnat's piss but laws do need to be precise.

 

BTW does anyone know how this 2m3 is defined, is it a bulk load or solid wood?

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2 hours ago, openspaceman said:

What worries me about this chart is that woodworkers and joiners generally use moisture content referenced to the dry weight of wood, for burning we usually reference the wet weight of wood and I cannot see on this site which moisture content they are using.

 

 

No idea but this is the page I got the picture of the chart from 

WWW.WOODPRODUCTS.FI

Wood is a hygroscopic, meaning it is a material that absorbs water. Water gets into wood in three ways: as a fluid through...

 

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53 minutes ago, Woodworks said:

No idea but this is the page I got the picture of the chart from 

WWW.WOODPRODUCTS.FI

Wood is a hygroscopic, meaning it is a material that absorbs water. Water gets into wood in three ways: as a fluid through...

 

I'm glad you found that, it confirms that the equilibrium moisture content tables you are reading are based on the  moisture content  on a dry weight basis so if we take as an example for you of 90% RH and 10 degrees C from your chart that gives an equilibrium moisture content of ~23% dry weight basis, which is a moisture content of 18.7 on a wet weight basis, quite a bit under the 20% target.

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23 minutes ago, openspaceman said:

I'm glad you found that, it confirms that the equilibrium moisture content tables you are reading are based on the  moisture content  on a dry weight basis so if we take as an example for you of 90% RH and 10 degrees C from your chart that gives an equilibrium moisture content of ~23% dry weight basis, which is a moisture content of 18.7 on a wet weight basis, quite a bit under the 20% target.

I never realised there were 2 systems. Do we actually know which system they are using? Also I never seen this mentioned with moisture meters. Mine is I think developed for furniture but cant be sure

Edited by Woodworks
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This might be of use:

https://www.forestresearch.gov.uk/documents/1979/FR_BEC_Testing_Moisture_Content_Simple_method_2011.pdf

 

 

Quote

The moisture content (MC) of a piece of wood is defined as the weight of water expressed as a percentage of the weight of the wood either the total (wet) sample weight (wet basis) or the dry wood weight (dry basis) All fuel calculations are carried out on a “wet basis” (MCwb)
The wet basis moisture content is a measurement of the proportion of the sample which is water expressed as a percentage of the total sample. For example if the wood in a sample weights 50kg and the water in the sample also weight 50kg, then the total MC of the sample would be 50% as half of the sample is water.
The MCwb = (the weight of water in a sample/ total initial weight of the sample)x100

 

“Dry basis” is expressed as the percentage of the oven dry weight of the wood. For example, if the wood in a piece of timber weights 50kg and the water also weighs 50kg then the dry basis moisture content is 100%. The main advantage of this method is that the oven dry weight of the wood remains constant. This method is the standard used by many of the organisations doing research on wood, as well as building surveyors and architects. (It is rare to use dry basis measurements when talking about woodfuel)
The MCdb = (Weight of water in a sample/ oven dry weight of sample)x100


 

Edited by Paul in the woods
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Makes you laugh with a limit of 2m3 do we assume thats 2 builders bags as they always sell them as a m3.

What I thought also, I assume its what they are implying , but who knows....they probably haven't actually planned the policy  in proper detail...

 

Festmeter Schüttraummeter or Schichtfestmeter?

 

Bet teh Germans wouldn't tolerate this half arsed ambuiguity ?

 

 

 

 

 

 

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I thought these bullshit bills where a thing of the past that where only made up in Brussels, apparently not.

I think this is less about pollution and more about Government vat losses on gas and oil as more people turn to wood fuels.

How much is it going to cost to set up a department to police and deal with this issue?

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