I love this. So now it's your responsibility to manage what the client might do or what might happen to this occupancy in 3, 5, 10 or 20 years? With all due respect, that's not your responsibility and beyond that, where does it end? I had a fire official try to require a .45/3000 s.f. design in a 3-story office one time because she pointed out that if a future owner or occupant cut out part of the second and/or third floors they could theoretically use the building for high-piled storage some day - do you agree with that?
I hope not, but if you squint and look at it in just the right light it's the same thing as saying that there's some value to future owners or tenants if you make the installer hold velocity to some arbitrary level or not allow the efficiencies associated with the hydraulic design of QR sprinklers. For the past 5 days including the weekend, a stream of extremely articulate rebuttal has been running through the forum that casts aspersions on the validity of velocity limits, yet at least two of us cling to this notion that there's a benevolent value to society (?) if we dig in and obstinately insist that there is a basis for an archaic requirement such as this. It has even been pointed out that the original basis for your opinion, that it was once in NFPA 13, isn't accurate yet some would cling to the notion that it was ever codified to begin with. Mario, I believe your opening line is a misstatement - "Usually the customer changes the occupancy or the use of the building or certain areas of the building or increase the size of the building." That is not true; SOMETIMES a building gets enlarged and sometimes its use and/or occupancy changes, but I'll bet that it's 1% of the time, maybe 2% (I would value the opinions of others on this point.) A tilt-up shell is a warehouse is a warehouse is a leased light industrial or heavy industrial use, is a warehouse. And an office shell may have a small deli or mini-mart, but for the life of that building it's an office shell. Same for retail (admittedly there is more to that type of project in terms of design criteria, but it's still going to be a mercantile project for it's entire life span). Same for a courthouse. Same for a high-rise condo or a mid-rise condo. Or a hotel. Or, or, or ... It is NOT the responsibility of the AHJ to read the tea leaves and ordain the a project should be designed in accordance with any code or standard except those that apply to what it is or is proposed to be as submitted. You need peace of mind to sleep well at night? You can have it. Make it the safest hotel we can reasonably make it according to what's in writing the day they submit for permit. But protecting a hotel with arbitrarily oversized piping or a pump that it doesn't need or three times the amount of water in the system than it requires only costs our community money and there is not tangible benefit no matter what weird science you throw at the issue. Steve Leyton Protection Design & Consulting -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Monday, January 15, 2007 1:36 PM To: [email protected] Subject: Re: max velocity Mr. Rahe Loftin,P.E.: I agree with you. Usually the customer changes the occupancy or the use of the building or certain areas of the building or increase the size of the building. If the piping is at the beginning small then the customer is penalized because he has to revamp the system. There are some agencies that specify 20 fps to allow them to expand the building; to have a margin of safety if the city drops the pressure;to be sure to have 7 psi at the last sprinklers; to be sure that the highest branch has 15 psi. The water pressure will compensate if high velocities are used if the city would provide more pressure. The Hazen Williams formula was developed at 3 fps for open channels. Keep up the good work. Thank you. Mario Berrios, P.E. -----Original Message----- From: [EMAIL PROTECTED] To: [email protected] Sent: Mon, 15 Jan 2007 4:03 PM Subject: RE: max velocity I suggest that Schedules 10 and 40 domestic pipe and (with a few quality imports excepted) domestic fittings as well, are the best way to assure the proverbial 50-year building. But the rest of it is just a waste of taxpayer money, as far as I'm concerned - especially velocity limits or any other unsubstantiated provision that only adds cost to the construction without tangible benefit. Our firm does a measurable percentage of work in the Federal jurisdiction (NAVFAC and ACOE, primarily) as well as State of California projects for schools and licensed healthcare. Although this work contributes to our bottom line and puts food on the table, I always marvel at how public money seems to be "cheaper" than private money - at least to the folks who spend it. Steve Leyton Protection Design & Consulting -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Monday, January 15, 2007 10:55 AM To: [email protected] Subject: RE: max velocity Folks, Here is some more food for thought. I provide the sprinkler specification for all of my federal projects. I use 20 fps velocity as a limit and a maximum C of 100 to insure that I have a system that has a chance to last for the life of the building (approximately 50+ years). Our buildings are always being changed with the sprinkler system being drained and modified many many times by all sorts of contractors, from the best to the worst. Once the building is constructed and occupied, the local GSA service center does all of the work in the building, usually with the lowest bidder. Therefore, we need some sort of hedge against all of this. Once the building is built, it is out of my control. I see no problem specifying these limits as long as everyone is bidding the same job. Any suggestions? Thank You Rahe Loftin, P.E. Region 7 - GSA Office - 817-978-7299 Fax - 817-978-8644 Cell - 817-371-3102 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum ________________________________________________________________________ Check out the new AOL. Most comprehensive set of free safety and security tools, free access to millions of high-quality videos from across the web, free AOL Mail and more. _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
