On Mar 4, 2011, at 11:07 , David Mann wrote: > On Mar 5, 2011, at 5:42 AM, John Sessoms wrote: > >> I'm curious. Is there any way to build a reinforced chimney that wouldn't >> likely come down in an earthquake? > > Anything's possible with a big enough budget ;) > > I think the key is to build a little bit of flexibility into it. Or attach > it to the structure as much as possible. Ours stuck out a long way, it would > have been better if it was built on the gable wall like some others in our > street. I think there is or was a regulation that the top of a chimney has to > be taller than the apex of the roof otherwise the air currents carry the > smoke downwards. Or something like that. I could be completely wrong. > > These days a lot of wood burners are free-standing and they run a metal flue > straight up through the ceiling. It's almost indestructible and you get > better efficiency from the extra heat radiating from the flue itself into the > room.
If the chimney was constructed of bricks with holes in them, and could be properly aligned, rebar could be run down through them to at least the firebox area. Eight to 16 rebar would certainly keep the chimney standing, lessening the damage and danger in the event of a quake. At least up to the violence that would take the chimney off at the firebox, and the wall(s) it was braced to. During the Seattle Nisqually quake of 2001, my sister's chimney broke about 4 feet down from the top in a jagged line stepping down the brickwork. But it was only displaced about an inch because the old tile flue pipe had been strengthened with a steel pipe insert some years before. A mason came out and removed the shifted top, saving the bricks, then using them to rebuild the upper portion. While there he re-pointed the entire chimney which was mostly out side of the house. He had shown us with a screwdriver that the 70 year old grout had mostly become loose sand, the binder having evaporated. Joseph McAllister pentax...@mac.com “ The early bird gets the worm, but the second mouse gets the cheese.” — Kevan Olesen -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
