Double crown board boards

[Newbeeneil]

yes a bit like it but actually a lot more effective. Its because for two horizontal plates, with an air gap, and a temperature difference, the air gap has to be bigger than a certain size for convection to start. If I have do the calcs right, bee space is very close:10mm is good for 19 C temp difference between the inside surfaces .9mm 24c difference 8mm 33C difference

Very interesting. So, if I took a standard crown board with the holes sealed, a 8mm rim on top and sheet of correx (plastic but cheap.) sealed on top how would that compare with say a thickness of PIR?

 

[Newbeeneil]

Hmm, a former member on here was adamant that wool was perfectly dry. To be honest, I have no doubt that wool fibres are waterproof but it's the gaps inbetween that tend to hold water.
Having spent many a day out in the driving rain dressed in tweed from head to knee (with wool stockings from knee to toe) I've often been surprised how heavy it becomes and how much water I bring into the house at the end of the day.

The dampness I experienced was all on the top fibres and I had no seemingly damp crownboards

 

[user 6228]

Very interesting. So, if I took a standard crown board with the holes sealed, a 8mm rim on top and sheet of correx (plastic but cheap.) sealed on top how would that compare with say a thickness of PIR?

The way to work it out is the size of the air gap. The air gap will have 0.0265 W/(mK) and PIR is 0.023 (PIR uses a higher molecular wt gas)If you used 2mm correx you would be close to the equivalent of 10mm PIR.

 

[user 6228]

Hmm, a former member on here was adamant that wool was perfectly dry. To be honest, I have no doubt that wool fibres are waterproof but it's the gaps inbetween that tend to hold water.
Having spent many a day out in the driving rain dressed in tweed from head to knee (with wool stockings from knee to toe) I've often been surprised how heavy it becomes and how much water I bring into the house at the end of the day.

Quite a few insulation materials are like that. Thermalite blocks that are soaking wet are anything but light. After building the workshop I had a big surplus of blocks left over. I sold them on ebay and the buyer turns up with small van, he loads them up and the van was on its bump stops well before it was full. The blocks had been left outside.

 

[Erichalfbee]

Having spent many a day out in the driving rain dressed in tweed from head to knee (with wool stockings from knee to toe) I've often been surprised how heavy it becomes and how much water I bring into the house at the end of the day.

What? No Barbour?

 

[jenkinsbrynmair]

What? No Barbour?

only for fishing and as a backup whilst hunting. Barbours get as stiff as a board in torrential rain and hampers your gun mount and swing

 

[JamezF]

The dampness I experienced was all on the top fibres and I had no seemingly damp crownboards

I wonder if the wool wasn't providing sufficient insulation and condensation was forming at the boundary between the warm air in the wool and the cold air above it?

James

 

[Poly Hive]

As I recall the sawdust etc was offered to the hives sewn inside hessian. In fact many colonies had a hessian cover on the top bars esp in double wall units and notably the Glens.

It's worrying now that I am reminding people of the history, shows I am getting on. I knew a man who personally knew Mr Wood. You will better know him as Woodi. The man who stumped up £6000 in the late 1920's for the research into acarine. And here's something to make you think...

£100 in 1928 is equivalent in purchasing power to about £8,037.51 today, an increase of £7,937.51 over 95 years. The pound had an average inflation rate of 4.73% per year between 1928 and today, producing a cumulative price increase of 7,937.51%.

So generous or what at just shy of half a million?

PH

 

[Newbeeneil]

I wonder if the wool wasn't providing sufficient insulation and condensation was forming at the boundary between the warm air in the wool and the cold air above it?

James

I’m sure that it the case. The dew point was at the time of the insulation.

 

[Erichalfbee]

only for fishing and as a backup whilst hunting. Barbours get as stiff as a board in torrential rain and hampers your gun mount and swing

Good job we have Gortex and Paramo these days.

 

[jenkinsbrynmair]

Good job we have Gortex and Paramo these days.

to think Barbour made all the outer clothing for the big Arctic and Antarctic expeditions!
I'm on my second barbour now - my mother bought my first one for me when I was fifteen, wore it to the office when I started in SW England HQ in 1988, just as they became de rigeur for the yuppies and caused some jealousy as even then it was obvious I'd had it for some time and not just as a fashion statement it had completely worn out by the time I was thirty (although I still used it for some time after that). the replacement is still going strong though nearly thirty years later

 

[fian]

to think Barbour made all the outer clothing for the big Arctic and Antarctic expeditions!
I'm on my second barbour now - my mother bought my first one for me when I was fifteen, wore it to the office when I started in SW England HQ in 1988, just as they became de rigeur for the yuppies and caused some jealousy as even then it was obvious I'd had it for some time and not just as a fashion statement it had completely worn out by the time I was thirty (although I still used it for some time after that). the replacement is still going strong though nearly thirty years later

It is true that two hundred years is enough time to consider the quality of the Barbour brand, but it seems a bit lacking compared to the ethnic wetsuit of my land made entirely of dry reed and with a few more centuries of tradition.

 

[Erichalfbee]

It is true that two hundred years is enough time to consider the quality of the Barbour brand, but it seems a bit lacking compared to the ethnic wetsuit of my land made entirely of dry reed and with a few more centuries of tradition.

Do you keep bees in that?

 

[fian]

Do you keep bees in that?

No, that was (it is completely out of use) a suit for people to avoid getting wet on stormy days in high mountain areas. For the bees we have cork hives, you can see one on the left of the screen in the video I posted the other day.

 

[Erichalfbee]

I know. I was joking.

 

[Anduril]

If what you are looking for is something similar to plastic foams in a natural version, the cork or bark of "quercus suber" should be highlighted.
just as light, waterproof, biodegradable and with a similar value of thermal resistance.

Brother Adam used cork above the crownboard.

 

[user 6228]

Brother Adam used cork above the crownboard.

have you got a picture or diagram of what he actually used. I havent been able to find anything. I have a book which talks vaguely about it. I'm expecially interested if he used top ventilation or not. I have the same trouble with US originated papers as they dont often state whether they are ventilating or not.

 

[Anduril]

have you got a picture or diagram of what he actually used. I havent been able to find anything. I have a book which talks vaguely about it. I'm expecially interested if he used top ventilation or not. I have the same trouble with US originated papers as they dont often state whether they are ventilating or not.

Sorry Derek, it is only what I have read from his books. I think they were 2" thick.

 

[user 6228]

Sorry Derek, it is only what I have read from his books. I think they were 2" thick.

When I do talks i sometimes get "what about brother adam" he didnt get on well with insulation. The other failure for insulation i can find used top vents, The physics says top vented insulated will be bad news. The only allusion is that BA followed Canadian practice. Does that mean top vents ?

 

[pargyle]

to think Barbour made all the outer clothing for the big Arctic and Antarctic expeditions!
I'm on my second barbour now - my mother bought my first one for me when I was fifteen, wore it to the office when I started in SW England HQ in 1988, just as they became de rigeur for the yuppies and caused some jealousy as even then it was obvious I'd had it for some time and not just as a fashion statement it had completely worn out by the time I was thirty (although I still used it for some time after that). the replacement is still going strong though nearly thirty years later

In a previous job I was the commercial director of a company that renovated and refurbished wax jackets ...including Barbours. ...you would not believe the state of some of the coats we were sent... holes, pockets missing, press studs gone, zips broken and the cotton as dry as sticks. It was a 100% customer satisfaction business ... we never got a return. We breathed new life into waxed garments that were well over 30 years old.

We did a naval coat that had been used by someone on the Russian convoys and we thought that was the limit - then, two weeks later we were asked to restore a World War 1 trench coat that had hung in a shed for 50 years on an allotment and used every winter ! It went to a museum ...