Yesterday, 10:37 AM
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#131 (permalink)
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Somewhat crazed
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What I am hearing from possibly accurate sources is: you get this constant hot mass of embers hitting burnables. Duh. Raises the point of attack to burnable temperatures. Typically eaves and vent holes, but siding and also decoration. 20 year old wood has a lower ignition point, maybe only 250 degrees. lots of these places had oil based paint and varnishes. Add a resin bearing bush of any type and there is an attack point. Pretty much all the surviving homes were covered in stucco or concrete block construction and had airgaps with no vegetations against the house.
Just so you know: if you do the roof sprinkler thing, you need a potload more than just wet, think monster rain storm. Swimming pool source, and fuel powered genset. All the typical attack points are still dry because the roof is designed to do just THAT. Knew a crazy enginneer in Laurel canyon that survived a fire with a commercial roof fire sprinkler system outside, but his pool was dry, the genset cooked (literally)
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Yesterday, 02:51 PM
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#132 (permalink)
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Master EcoModder
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Quote:
What I am hearing from possibly accurate sources is: you get this constant hot mass of embers hitting burnables. Duh. Raises the point of attack to burnable temperatures. Typically eaves and vent holes, but siding and also decoration.
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Embers don't have mass, so they should flow around any compound curve surface. Avoid overhangs.
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.Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster
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Yesterday, 04:51 PM
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#133 (permalink)
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Human Environmentalist
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Did a little more looking, and it seems embers igniting nearby shrubbery, and then catching window frames or eves on fire is the most common method of ignition.
https://www.frontlinewildfire.com/wi...catch-on-fire/
Looks like rooftop sprinklers can be highly effective.
Quote:
In the Ham Lake wildfire in 2007, over 72 percent of the properties that survived the fire were fitted with rooftop sprinkler systems, and only one structure with a sprinkler system was destroyed. This demonstrates that when properly installed and maintained, rooftop sprinklers can significantly increase a home’s chances of surviving a wildfire.
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...and the forest service says wildfire prevention is the cause of catastrophic fires.
Last edited by redpoint5; Yesterday at 06:24 PM..
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Yesterday, 06:02 PM
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#134 (permalink)
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Thanks for that. I was thinking about adding agents to the water. Some sort of gelling agent?
Just as an arch benefits from a massive keystone, a dome would benefit from a water tank at it's summit. To pretension the shell and strengthen it.
Possibly toroidal around an oculus that has a cupola that can be lower to close it?
edit: I hear Blender calling to me. I can feel the frustration already. The current nodel I'd like to emulate is at Why Can’t American Cities Build 3-Flats Anymore??t=130. Beige monochrome on a reflective grid.
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Last edited by freebeard; Yesterday at 06:07 PM..
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Yesterday, 06:32 PM
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#135 (permalink)
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Human Environmentalist
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Quote:
Originally Posted by freebeard
Just as an arch benefits from a massive keystone, a dome would benefit from a water tank at it's summit. To pretension the shell and strengthen it.
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Suspend the water tank inside, and it acts as an earthquake counterweight and thermal buffer.
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Yesterday, 08:01 PM
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#136 (permalink)
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Master EcoModder
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Play your cards right and it could become a tracking solar collector.
Quote:
ccinnolab.org
The Solar 'Magnifying Glass'—Spherical Solar Collector
The spherical collector also produces double the amount of yield of conventional solar panels, thanks to an additional feature in its design: Its dual-axis solar tracking system allows it to rotate according to the position of the sun, so that sunlight at any time of the day can be harvested.
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Unfocused sky lighting could pass through to light the interior. Explosive bolts on the 'eyelid'
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.Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster
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