I might be wrong but it looks to me like the building might not be a high rise?
bmlxd40 said:
The roof manifold is at an elevation of 85'.
Correct me if I am wrong but isn't a high-rise building defined in Chapter 2 of the IBC as a “building with an occupied floor located more than 75 feet (22 860 mm) above the lowest level of fire department vehicle access."?
For the record, being the coward that I am, I would never make the decision whether or not a building is a high rise as that would be practicing architecture without a license which, especially you a layout technician is wrong, could get the company into a whole lot of trouble.
One thing people need to recognize is Georgia has some rather strange rules that don't exist anywhere else in the country and they can be found here:
120-3-3 State Minimum Fire Safety Standards - effective 01-01-2015
That is the last published rules.
Current state minimum standards said:
We are interested in the changes to NFPA #14 which begins at the bottom of page 43:
(13) NFPA 14, 2013 Edition, Standard for the Installation of Standpipe, and Hose Systems
Modifications:
(a) Modifications to Chapter 1:
1. Delete Section 1-1 in its entirety and substitute in its place the following:
“1-1 Scope. The State's minimum requirements for standpipes shall be established by the IBC (Refer to Table 102.13, CODES REFERENCE GUIDE) of the International Fire Code, as adopted by Chapter 120-3-3 of the Rules and Regulations of the Safety Fire Commissioner). In addition, the requirements for occupant hoses are eliminated for new and existing buildings subject to the approval of the authority having jurisdiction. Where the installation of standpipes and /or hose systems is required, this standard covers the minimum requirements for the installation of standpipes and hose systems for buildings and structures. This standard does not cover requirements for periodic inspection, testing, and maintenance of standpipe systems. (See NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems.)”
(b) Modification to Chapter 7:
1. Delete 7.8.1 in its entirety and substitute in its place the following:
“7.8.1 Hydraulically designed standpipe systems shall be designed to provide the waterflow rate required by Section 7.10 at a minimum residual pressure of 100 psi (6.9 bar) at the outlet of the hydraulically most remote 2-1/2 inch (65 mm) hose connection and 65 psi (4.5 bar) at the outlet of the hydraulically most remote 1-1/2 (38 mm) hose station.
7.8.1.1 Where the local Fire Chief or local Fire Code Official having fire suppression jurisdiction permits lower than 100 psi (6.9 bar) for 2-1/2 inch (65 mm) hose connections, based upon local suppression tactics, the pressure shall be permitted to be reduced to not less than 65 psi (4.5 bar).
7.8.1.2 Where the building is protected throughout by a supervised automatic sprinkler system and the building is not a high-rise, as defined in 3.3.5, the minimum residual pressure provisions shall not be mandatory when the standpipe system piping is a minimum of eight inches (8”) nominal diameter.
7.8.1.3 Existing high-rise buildings, as defined in 3.3.5, that are protected throughout by a supervised automatic sprinkler system shall be permitted a reduction of the minimum residual pressure requirement of 100 psi (6.9 bar) at the hydraulically most remote 2-1/2 inch (63.5 mm) hose connection to 65 psi (4.5 bar).
7.8.1.4* Manual standpipe systems shall be designed to provide 100 psi (6.9 bar) at the topmost outlet with the calculations terminating at the fire department connection. ”
2. Delete 7.8.2.1 in its entirety and substitute in its place the following:
“7.8.2.1 Pipe schedule designed standpipe systems shall have piping sized in accordance with the pipe schedule in Table 7.8.2.1 to provide the required waterflow rate at a minimum residual pressure of 100 psi (6.9 bar) at the topmost 2-1/2 inch (65 mm) hose connection and 65 psi (4.5 bar) at the topmost 1-1/2 inch (38 mm) hose connection.
7.8.2.1.1 Where the local Fire Chief or local Fire Code Official having fire suppression jurisdiction permits lower than 100 psi (6.9 bar) for 2-1/2 inch (65 mm) hose connections, based upon local suppression tactics, the pressure shall be permitted to be reduced to not less than 65 psi (4.5 bar).
7.8.2.1.2 Where the building is protected throughout by a supervised automatic sprinkler system and the building is not a high-rise, as defined in 3.3.9, the minimum residual pressure provisions shall not be mandatory when the standpipe system piping is a minimum of eight inches (8”) nominal diameter.
7.8.2.1.3 Existing high-rise buildings, as defined in 3.3.9, that are protected throughout by a supervised automatic sprinkler system shall be permitted a reduction of the minimum residual pressure requirement of 100 psi (6.9 bar) at the hydraulically most remote 2-1/2 inch (63.5 mm) hose connection to 65 psi (4.5 bar).”
3. Insert a new subsection 7.12.3.4 to read as follows:
“7.12.4 Location. The location of fire department connections shall be approved by the Fire Chief as set forth in subsection 501.5 of the International Fire Code, as adopted by Chapter 120-3-3 of the Rules and Regulations of the Safety Fire Commissioner.”
(d) Modification to Chapter 10:
1. Add a new subsection 10.1.3.1 to read as follows:
“10.1.3.1 A letter certifying that all pressure restricting and pressure reducing equipment is installed and set per NFPA requirements and manufacturer’s instructions shall be presented to the inspector along with test certificates at the time of final inspection.”
(e) Modification to Annex A:
1. Renumber A.7.8.1.1 to A.7.8.1.4 to read as follows:
“A.7.8.1.4 It is not the intent of this standard to provide an automatic water supply for manual standpipe systems. Manual standpipe systems are designed (sized) to provide 100 psi (6.9 bar) at the topmost outlet using a fire department pumper as the source of flow and pressure.”
With the exception of an open parking garage I have never been allowed to install a manual standpipe system in the State of Georgia. I haven't seen it lately, haven't bothered to look as long as the state gives me my 8" out, but I do believe there is something in the Georgia version of the IBC that only allows manual standpipes in open parking garages. I know I saw it once but to find it again I would really have to do some serious looking.
And the reason I asked if this building was a high rise there's this little gem that, as far as I know, is unique to Georgia:
7.8.2.1.2 Where the building is protected throughout by a supervised automatic sprinkler system and the building is not a high-rise, as defined in 3.3.9, the minimum residual pressure provisions shall not be mandatory when the standpipe system piping is a minimum of eight inches (8”) nominal diameter.
I've done this a number of times where in a four or five story motel I can do away with the fire pump completely as long as I run the entire standpipe in 8" pipe and this is from beginning to end. The way I read it if all your pipe is 8" you could have one psi of residual pressure at the roof manifold and you are good to go.
Trying to remember but over the past 10 years I know I have done at least half a dozen four and five story motels that have standpipes, that have typical city static pressures of 50 psi and and as the building is not a high rise all these have been approved and half of them were reviewed and approved by the state fire marshals office in Atlanta.
The 8" rule really comes in handy around Savannah where the local fire officials deem all electric is not reliable citing hurricanes. Yep, you do a fire pump in Savannah it will be diesel or have an electric backup generator with automatic transfer switch. Given this running the standpipe all in 8" is always the less expensive way to go.
I got one coming up right now a four story motel, a standpipe is required (fourth floor over 30') and due to some architectural trade offs we have a full NFPA #13 system. To compound issues the entire building is constructed of TJI's so running any large pipe through the building is a no go. How does one hang 8" from any wood structure mess less composite wood joists?
I have a backflow in the front yard where I place the fire department connection and then run 8" underground to each stairwell so the only place I have 8" is the stairwell and it is 8" all the way up to and including the roof manifold.
And I have heard of people in Georgia going with manual standipes in other than open parking garages and getting away with it. I would really, really like to know how they do this? Anyone give me some guidance on this?
Back to the original building where the ceiling of the top floor certainly is no higher than say 82' given the roof manifold is at 85'. At 82' given city water pressure of say 50 psi at sprinkler demand we would still have 35 psi at the top floor. Yeah, the sprinkler pipe might have to be increased a bit considering Georgia will be demanding a 10 psi "safety factor" in any calculations but top floor of an office or hotel certainly wouldn't be impossible.
Are RPZ's required on all fire sprinkler systems or only ones having a fire pump? Rules around Georgia can change a lot depending on jurisdiction.
If the building is not a high rise another option might be to run the standpipe in 8", we're already running 6" so it isn't that much of an increase, having a separate riser in a stairwell for sprinkler only. For the sprinkler riser use a 250 gpm @ say 60 psi pump? Sometimes this works out even better if the local authority requires hose valves on intermediate landings anyway. So give them their hose valves on the intermediate landings and run 3" up on the main floors with a floor control valve.
