Fire alarm in 3 floor sprinkled office building.

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Your absolutly right. I will be doing as builts. I first need to find out if the wires were run as per the drawings and document all of the points.

As for the Annunciator, is there somthing that im missing as far as why it will need to be redone? It was speced for the lobby in the original and I was just going to leave it the same on my newly submitted plans. Is that alright?

I was reading some other posts on class A vs class B and it sounds like it comes down to designers choice. If the building can not be bothered with down time then class A is prefered. Any thoughts on this.

My other thought is that since this was originally signed off as a conventional system then class B wiring will be alright. I of course will double check all of this, but wanted to hear all of your opinions.

Thanks,

Joel
 
I?ll touch on a bunch of stuff. Hope it helps.

I don?t know if I can post a link or not so I won?t. I would recommend if Mike Holt has a fire alarm training book get it. If not try to Google National Training Center Charles Aulner. He has a good Fire Alarm book that explains the basics very well.

You can read all the codes you want, but make sure you read the installation instructions for whatever brand fire alarm you are installing. Some will require different types of wire such as shielded vs non-shielded on addressable systems. Most new systems are going towards non-shielded wire.

The National Fire Alarm Code only tells you how to install the devices if another building code requires you to install them. It does require in some places that certain things be installed such as a smoke detector to protect the panel. Some areas use Life Safety Code 101 and some use other codes like the International Building Code. Don?t forget article 760 of the NEC.

Most systems are class B from my experience unless it is a government job or hospital or airport.

Some conventional systems can be wired class A or class B.

You can T tap most addressable systems but be careful to follow the wiring specs for the brand. Some have a limitation of so many taps and total wire distance. You cannot T tap any conventional system that I know of. Conventional systems supervise with the end of line resistor. If the panel sees the resistor the panel is happy. If you T tap off that circuit a wire cut to one of the branches would not put a trouble on the panel but would disable some devices. An addressable system supervises by talking to the devices. Even if a T tapped branch wire is cut, the device will stop talking to the panel and cause a trouble. I don?t know of any systems that allow T tapping on the horn/strobe circuits.

You said you are doing elevator recall. That can be difficult to do properly with a conventional system. Read the requirements on elevator recall in the National Fire Alarm Code. There are a few paragraphs on it. Elsewhere in NFPA 72 you will see that the relays need to be located within 3 feet of the elevator controller. This is to limit the distance of unsupervised wiring to the controlled circuit. It?s easy to install addressable relays there, but it?s hard to meet that requirement with a conventional system with relays located in the panel or by using smoke detectors with built in relays.
 
Joel P said:
Your absolutly right. I will be doing as builts. I first need to find out if the wires were run as per the drawings and document all of the points.

As for the Annunciator, is there somthing that im missing as far as why it will need to be redone? It was speced for the lobby in the original and I was just going to leave it the same on my newly submitted plans. Is that alright?

I was reading some other posts on class A vs class B and it sounds like it comes down to designers choice. If the building can not be bothered with down time then class A is prefered. Any thoughts on this.

My other thought is that since this was originally signed off as a conventional system then class B wiring will be alright. I of course will double check all of this, but wanted to hear all of your opinions.

Thanks,

Joel
Click to expand...


leave FAAP where it was signed off at.
I install three two wires to them
1. power (24v)
2. EIA 485 in (For FACP to communicate to unit)
3. EIA 485 out (For unit to control FACP from remote location)

Its usually located at the main entrance to the building so the FD can see where prob. is and go right to it.


So far the only time I have used shielded cable was for a NAC circuit that was a Speaker/Strobe.
 
Joel P said:
I reciently took on a trim out of a fire system from a company that went out of business, and upon looking over thier plans they had it for a non sprinkler system. Well this is a sprinkled building so I will need to go through a plan review to update it.

Now as a new business owner I am figuring out the whole process (Trial by Fire:) as I go and i have been told that I dont need the pull stations that were specified nor the smoke detectors since this is a class B building with sprinklers. What are the facts with this? I was looking through the NFPA72 and was having trouble identifying what they are referring to.

I do know that I will need to add flow, tamper and an elevator recall to the system. non of which were added before. I also have a door system with a crash bar and battery back up.

Any help is appreciated.

thanks,

Joel
Click to expand...

If it is a B- Business classification and you are adding a sprinkler system then their is an exception that says you do not need the pull stations again if fully sprinkled per NFPA 13. However, if it is a required sprinkler system then you still need atleast one pull station at the location specified by your local AHJ. You would also indeed need to add the tampers and flows to the system and make sure your notification devices are at the proper placement and compliant to IBC 907.9.1 and 2.
 
Class A and B:

Class A is better obviously, but if the rock is up, and the GC isn't paying for news holes leave it, if thats the way it was approved.

Besides a true class A has minimum seperation distances for the feed and return leg and most guys don't pay attention to that.

I have an AHJ that requires ALL circuits to be class A. No exceptions, doesn't matter the occupancy. Ask before you bother to change it.
 
Thank you Halleron for the referrals. I will check out the material that you mentioned. I do have alot to learn, and will get there. It just takes time as all of you know, im sure very well.

All of the wiring is already pulled for class B wiring, with the exception of any T taps that I may need to run or the elevator recall. These are short runs that will be surface run with the same room or one room over.

I have been working with a local fire vendor pretty closely now and he is hellping me design a hybrid type of system that will give me the addressable runs for the T tap locations and conventional runs for connection to use non addressable devices to save money.

I now have the plans redesigned and will get this to the city for approval after I get my spec sheets and loads figured out.

I think it is all looking up now. I know I have some work ahead of me.:D
 
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