Tom, The threat is definitely real. I've seen it. Light up the BBQ & it spreads to the exposed, cantilevered decking above and then has the potential of breaking through the blocking and getting into the interstitial space between floors or into the attic. I'm just not so sure that the IBC approach will have any effect at all and surely none where there isn't any overhead projection (and what have we here on the forum determined to be a significantly large enough "heat collector?"). Then there's the how far back into the building do you need to take the feed for the head in steel so as to mitigate against freezing. Even out here in a relatively benign climate this has proven to be a problem. I'm impatiently waiting for my friend Mike Fitz to publish his study relative to this issue. I'm thinking your idea of running a separate riser for these heads is a good idea, whether a wet or dry riser determined by climate (I hate pipe in exterior walls), and wish I'd thought of it. Funnyish story. In these p[arts there's an insulation contractor currently trying to pass the blame for broken pipes onto the sprinkler contractor because the latter did not tell the former that the insulation needed to be between the cold side of the building and the pipes. So now we have to do structural calcs for the builder to prove his building can hold up our pipes, do soils calcs to prove our system won't sink the building (believe it or not, I've seen this), make sure the painter doesn't paint over plates that have embossed on them "Do Not Paint," AND make sure the insulating contractor knows that the insulation is supposed to be between the cold side of the building and all the stuff that doesn't like being too cold, like water & people. Time for another cup of coffee. I suggested to my wife the other day that we should be drinking our coffee from now on permanently in Sardinia. She thought it a good idea. All future correspondence shall be in ungrammatical Italiano. Arrivederci amico. Abbia un giorno piacevole.
On Sun, Mar 29, 2009 at 9:42 AM, Tom Duross <[email protected]> wrote: > Ron, you gotta take it easy with the coffee baby... > (Just kiddin', too bad you're so far away, I'd enjoy being your student but > that whole east coast-west coast thing, what would I tell my homies?) > We're now installing this system I originally posted about and the whole > thing does seem a little silly (bad adjective, maybe hypocratic is better). > I know the bbq is going to be located to the right (or left) end of the > porch or of the slider behind the fixed one, probably one of those plastic > organizers with all the tools alongside but the bottle (bomb) will be right > against the house (probably) with a spare alongside. > We're doing this to appease the bldg. insp. so they can have larger porches > (I asked proximity to property line but never got an answer but I think it's > within 3' with the addition) and so these balconies can be bigger (to hold > all kinds of things, kid of a new storage area) and now connect to the open > wooden stairs so in case homer waits too long to throw a match into the > barby and it flames, he's got some place to run. We're not placing a head > at the top, no overhang, no capture, and more importantly; the inspector > agreed it wouldn't do much. I gotta write that cya latter to him when I'm > done with this... > Two things that make my liability hairs tingle: Will the presence of a head > make these owners and future owners think it's safe to place 15/30# of > propane outside the thermopane glass filled opening and bask in the relief > of protection? Is someone thinking this is some type of opening protection? > I've written posts to this forum before about how some folks around here > think placing dry sidewalls over windows and doors constitutes an acceptable > alternative to a 15 system. Maybe the fact that there are SO many of these > installations in this town, it's becoming accepted? That's my problem but > getting back to the original topic, I'm just calculating for a "stack" of > heads to go off, 3 per riser. I'm running their psi/gpm requirements to > cover the width of their listed coverage because the length is nothing in > comparison. Maybe I should have calculated all 6 like an exposure system? > The more I think about it, the more I worry. > I think I got to get some verbiage into that note window of the co-made > binder they're askin for. (maybe I shudda taken it easy on the java myself) > > Tom Duross > > > > And Ed's comments bring us back to the size of fire. Sprinklers in > racks because we expect big fires in racks so big fires set off > sprinklers shielded by commodities above. No commodities above and we > have ceiling sprinklers with a ceiling above. There are apartment > buildings in the NW with no eaves so a head would need to be directly > above the barbecue to have any chance of going off. Now maybe if the > siding lights up the head will go and hold the fire at bay. Again, > it's the fire guys that have experience of how much wall can be > burning before the fire is beyond the ability of a sprinkler head to > contain and if the head would likely go off in time with nothing above > it to catch heat. I suspect this requirement didn't come out of any > NIST, FM or UL testing. I'd even bet it arose from a non-engineered > notion (guess?) on how to address a perceived problem. And I'd venture > to say it never was considered a property protection measure but > rather as a life safety augmentation, the lives we're trying to > augment the safety of being those of firefighters who have a tendency > to foolishly enter burning buildings or climb up on roofs and the > like. So the goal is sound and with merit but I'm unsure if the cost > (what is the installation cost of a gross or so of dry pendents for an > apartment complex?) is warranted if we have no data on the likelihood > of these top floor, uncovered units even operating when needed. Even > the lower ones tend to be installed beyond their listing so who's > liable if there's a failure? ICC for making a requirement knowing no > equipment to meet that requirement exists (every kitchen must be > equipped with one of those Mr. Coffee things that makes garbage into > plutonium like in "Back to the Future")? THe contractor (most likely) > for putting in equipment beyond its listing? The guy who left his > barbecue unattended (not likely since it seems to be un-American to > place the blame on the guy that actually was negligent)? I'm rambling > so I'll wrap. > > _______________________________________________ > Sprinklerforum mailing list > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) > -- Ron Greenman at home.... _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
