Dannos Limey Build (Suffolk UK)

[Laurentius]

Re: Dannos Limey Build (Suffolk UK)

If you're really worried about moisture, then paint it with two or three coats of an acrylic exterior paint, problem solved. Don't worry, be happy.

[Laurentius]

Re: Dannos Limey Build (Suffolk UK)

Mine's stucco with acrylic paint, because we have a rainy and typhoon season. Two years and no problems. If your's has stucco its recommended to allow it to cure for 6 months before painting.

[Laurentius]

Re: Dannos Limey Build (Suffolk UK)

Lastly, don't waste your time with a lamp! Its an oven, cure it with fire. The recommendation is small fires, followed by progressive larger and longer firing. If you're worried about moisture in the winter, use it all winter, I do, it really knocks the chill off.

[Bookemdanno]

Re: Dannos Limey Build (Suffolk UK)

Thanks Laurentius, i like your style! Xmas Wood fired Turkey it is!
I've added an amount of Magnesium Stearate to my final mix. Its a material used to coat tablets to stop them sticking and go down easier. I was told it gives an element of waterproofing without comprmising the vapour permeability. Finished the top coat this afternoon, tightened up the render, and packed it off to bed wrapped in plastic.

Many WFO in Japan?

[Laku]

Re: Dannos Limey Build (Suffolk UK)

If the vermicrete is still wet, and it should be since it takes weeks to dry, the steam will most likely crack your stucco. If not worse.

[david s]

Re: Dannos Limey Build (Suffolk UK)

By waterproofing the outer shell at this stage, you are making it even more difficult to remove the water underneath it. You will now have to take it really slow to remove the water or you risk cracking th outer shell. If you want to waterproof it then it is better to do it when you are sure the whole thing is properly dry. Good luck.

[Laurentius]

Re: Dannos Limey Build (Suffolk UK)

Hi Danno,

There are lot of WFO, here in Japan, but nearly all are without insulation or proper insulation. I talked to one guy who paid a structure engineer about $8,000 to make sure his wouldn't fall down, enclosed his dome with bricks and assumed the air within the enclosure would insulate. Another guy who owns a pizza shop, spends most of his time gathering firewood, his oven is made of massive stones, on a concrete slab, a real heat sink. I was going to teach him how to make sourdough bread, but he said, once the fire is out the oven is dead. By the way don't worry about the addition of the magnesium stearate, its only act as a lubricant, it has no waterproofing properties. Most of us know it by another name.(bathtub ring or soap scum)

[Bookemdanno]

Re: Dannos Limey Build (Suffolk UK)

hmmm, i was told to add Magnesium Stearate by a Lime supplier!
I think i'll trust their judgement. By the way that water beaded up on the surface and ran off on some other that i added it too, i think also backs up their statement. You're right in your statement thoug Laurentius.

I'm wondering why you'd get steam from the vermicrete layer? It'll have to get to 100 degrees celcius to generate it, so i'd be more worried about all the time i spent insulating the oven with blankets if its going to get that hot at the vermicrete??
You'd still not be able to touch the outer render?

Thanks for the concern tho guys, i will keep the seasoning slow going...hopefully!

Whats the worse that can happen? Another render layer?

[brickie in oz]

Re: Dannos Limey Build (Suffolk UK)

Whats the worse that can happen? Another render layer?

Apart from a major dome crack....well nothing.......

[Laku]

Re: Dannos Limey Build (Suffolk UK)

I'm wondering why you'd get steam from the vermicrete layer? It'll have to get to 100 degrees celcius to generate it, so i'd be more worried about all the time i spent insulating the oven with blankets if its going to get that hot at the vermicrete??
You'd still not be able to touch the outer render?

It gets hot because it's wet and there for the blanket below is wet. Water will transfer the heat and prevent the insulation doing what it's supposed to.

Once dry it would barely get warm. But as it is now it will get hot enough to generate steam.

And as it's closed inside the render it will take a lot more time to pass out the moisture than it would if not enclosed.

[david s]

Re: Dannos Limey Build (Suffolk UK)

Bookemdanno,
You have trapped a lot of water in that insulation layer, and have only left the vermicrete for a week to dry. You should be able to work out how much water is trapped in there if you look at the experiment I did with vermicrete on # 58. Ask yourself how much fire you'd need to boil that amount of water dry. However, fire will eventually drive it out. If the outer shell feels hot to the touch this will be your indicator that the insulation is still wet. Don't give the fire any more flame if this happens. Also if you see any steam rising from the oven back off with the flame. Long very gentle prolonged fires are the way to go. I'd guess you would need more than a dozen of these, but use the oven to do some roasting and baking along the way, just don't aim for the high temp pizza fire, unless you want a cracked outer shell. If it does it's not the end of the world, the outer shell is only to keep the weather from getting in and wetting your insulation. you can always render over it again.
Good luck,
Dave

[Gulf]

Re: Dannos Limey Build (Suffolk UK)

To David S.

Dave,
I work with steam on my day job. We use it for heat, pressurizing and as a means of lowering atmospheric pressure to almost a complete vacuum. Water droplets rapidly turning to steam take up a sht load more amount of space . I am paraphrasing you in this statement . It will also exert the same amount of force inwardly when collapsing back to the water droplet state.

.........

just don't aim for the high temp pizza fire, unless you want a cracked outer shell. If it does it's not the end of the world, the outer shell is only to keep the weather from getting in and wetting your insulation. you can always render over it again

.......

What are your thoughts on a relief hole from the outer shell to the depth of the fiber insulation layer to help relieve some of the forces? My build will incorporate a permanent relief at the apex of the dome which I hope will aid in current and future moisture problems One that could easily be sealed once the curing is complete. Even, in slowly ramping the curing fires up, would not a relief hole help give the moisture a place to go, which might help with a faster drying process?

Joe

[Laurentius]

Re: Dannos Limey Build (Suffolk UK)

Hi Joe,

I'm confused! I viewed your Web Album, and your build is according to plans. You have your finished dome insulated, then vcrete filled enclosure. It seems to me that your permanent relief, if it goes all the way to your ceramic blanket, will cause a cycle of wetting your ceramic blanket from the condensation of water vapors, when the moisture from the vcrete cools.

[david s]

Re: Dannos Limey Build (Suffolk UK)

I have incorporated a vent in the outer shell in the surround that supports the flue pipe, by making two terra cotta collars. It works pretty well, but you still need to eliminate most of the water after the initial build. If a lot of the water in the vermicrete layer decides to turn suddenly to steam the whole layer expands and a little hole at the top won't be enough if the vermicrete layer has already been covered with stucco/ render.

[Bookemdanno]

Re: Dannos Limey Build (Suffolk UK)

I'll just take it easy guys, i think. But, i failed miserably when i did that before!

My Hydraulic Lime based build allows a far greater ability for vapour to pass freely back and forth as is the old fashion way. Don't fight it, work with it.
The Magnesium Stearate adds a level of water resistance from the exterior but not as with Cement based products, a waterproofing layer both ways.
Think an animal fleece, such as sheeps wool and the Lanolin not a Tortoise Shell.

Thank you guys, i will hopefully take the seasoning as slow as i can.