I am cabling an old 6 story hotel and intend to use plenum cat 5e to make it fireproof. The customer wants to make the cabling tamper-proof. I am looking for a fire-proof,low-cost alternative to steel conduit. Most raceways are PVC and "fire-retardant". This means they burn at temps above, say 95 degrees, and when they burn they give off toxic gas. So I am thinking this would make my fireproof cable illegal for the firecode. I want to be safe and not have to redo the whole job if inspected. I will have about 10 cables per floor side, requiring 3/4" diameter (I think) feeding to a box that feeds 3 individual rooms. Anyone have any low-cost fireproof suggestions?
I can't find anyone that knows specifically what the fire codes are for telephone cabling or enclosures in the San Francisco area. Does anyone know?
Last question first. The AHJ or electrical inspector is the person to talk to BEFORE you plan this job since you have no clue.
As for the use of PVC, that would be up to the local codes which the AHJ or inspector will fill you in on. It is NOT fire retardant and neither is a plenum listed cable. They WILL burn but just not give off as much smoke as a non-plenum cable. So don't call them "fireproof"!
If it were me I would run everything in EMT and save money by not using a plenum listed cable and CAT5e.
-Hal
Hal's right. EMT with standard riser cable rather than plenum. Anything you're going to find that doesn't give off toxic fumes is going to cost a heck of a lot more than EMT.
While you're at it running the feeders, I would go 1" with ten cables just in the event that you need to fish another one at a later date. That many in 3/4" is going to be pretty tight.
I have to agree with the above. For the EMT, the larger the better. Words of experience.
Installing conduit might mean losing the job after funds are spent.I'm the one was concerned about "fireproofing"-Since I've never worked a job of this size, I want to be sure I'm not liable.
I did find some specs on SF wiring online-
https://www.archive.org/stream/gov.ca.sf.electrical/ca_sf_electrical#page/n21/mode/2up According to this, anything lower than 50 volts need not be enclosed in metal raceways, tubing, or wireways. I certainly would like to ask an authority. But,I've never had to work w an electrical inspector for low voltage telephone cabling. Is the HV electrical inspector the AHJ for low voltage? Should I talk to a fire inspector as well?
Even using something like metallic Wiremold you're looking at approximately 5-7 times the cost versus EMT.
Is this all to be surface mounted or some in drop ceiling/hard ceiling?
Yes, the electrical inspector is the electrical inspector. Point here is some jurisdictions will not allow the use of PVC pipe or conduit and that can be based on the occupancy. The electrical inspector would certainly know and I would talk to the building inspector also. And as long as you are talking to city hall I would check to see if a permit is required as well as an inspection. Might as well get this all cleared up before hand so you can decide if you want to do this.
-Hal
40% conduit fill is the NEC code but local codes may differ. Also, be careful to never use the term "fireproof". Plenum cable burns but just doesn't give off the same level of toxic fumes. Most fatalities in a fire are from smoke inhalation.
To tamperproof the cable it only needs to be protected (covered) from the IDF to fdr can (3 cables) = 15 ft and from the fdr can to the room (1 cable)= 6 to 15 ft each room. I was thinking about covering the plenum cables with metal "C"-shaped rods. Or-sub out the conduit work to a electrical contractor.
Of course the customer is pushing for the estimate and says he will lose funds if estimate not in by Feb. By the time an electrical inspector gets out there it will be weeks (months?) before he gets there. I'll find out today. Also, I need to ask customer permission-I don't want to be a whistle-blower- there are phone cables run out windows and down 5 stories in all the air spaces,exposed cruddy wires along hall ceilings, new security cameras installed w cat 5 and baluns using PVC and covered w PVC raceway in some places run alongside the telco cables, and new coax CATV neatly running down the air shaft. The only thing in conduit is the new HVAC (neatly done)= I would guess it cost $100k+ for the HVAC job alone and that's what customer wants to avoid..
I feel confident the plenum cable exposed should be ok and I don't see any problem giving customer an estimate for that at this point plus an estimate on PVC cable if he has conduit installed
At this point, I'll call customer to get permission to call city hall electrical inspector and call a sub to estimate cost on the conduit from IDF to rooms.
What do you think?
Just getting a job like this is a Godsend at this bad economy time. In better times I would just define my boundaries-I'll do PVC cables, electrical contractors install conduit and we'll do install afterward. But at this point in time, I've had to stretch my borders- used to be my company did phone systems, VM, paging & PAs and small networks. Now it's anything low voltage- add security cameras, computer programming and troubleshooting, CATV, and anything else low voltage.
This job is certainly bigger than my normal job size, but it's been good profit here and looks like a great opportunity. The security added is an issue we all will face, as is the low-cost alternatives.
I'm not doing business "as usual" in this economy and have made some adjustments= stretching technical boundaries, doing flat rates instead of T&M, and more negotiation. This job is a good example for defining or stretching boundarie
Well, now it's a different story if the existing is as bad as you say it is. I thought this was a respectable place.
We installed cabling in many such and much better buildings for the cable companies. We would use a PVC corner raceway run around the ceiling/wall juncture in all the hallways on each floor. Then we would punch through the back of it and through the wall into the apartments or units where needed. From what you are saying I see no reason you couldn't do the same thing.
Where did the "fireproof" requirement come from? Was it your idea or the owners?
-Hal
Late suggestion but just wanted to add that if the customer is afraid of tampering as in security to possibly recommend fiber optic cabling run but perhaps from the description of the building you mean a more mischievous security threat...
I suspect it's mischief and vandalism. That's usually the case in places like that but then again we haven't been told what this cable is for.
-Hal
I haven't had time to update, but here it is.The "fireproof" came from me. Customer wanted it tamper-proof- from angry tenants and saboteurs. This job was the first time I had to get an inspection and I got a little bit overcautious, I now believe.
Luckily, I ran into an old phone company workmate from the Pacific Telephone days at a reunion and it turned out he had a telco business here in San Francisco, and did jobs like this all the time. He advised me that 1. I do need a permit and that 2. plenum cables would be fine and standard PVC raceway is fine as well. Just as you say Hal, thanks.
I did my walkthrough with electrician today who will install sleeves and possibly a conduit in the busy ground floor and price out conduit from IDF closets to rooms on each floor. I will compare the pricing and almost for sure will go with the standard raceway afterward.
I appreciate the advice very much. Thanks all!
do not forget to take labor into account, if the sparky will run conduit for you it will be much faster then if you need to lay in your own raceway.
Just make sure there are pull strings and conduits are correctly ID'd!