Cost of fiber run between neighbouring office buildings

Hi folks,

I wonder if I can tap into some knowledge on the list and ask for ballpark figures on how much it would normally cost to run 2 fiber cables between 2 adjacent office buildings. I have a quote from a contractor, and I want to make sure i'm not getting totally fleeced.

The conduit is in place between the buildings.

The work entails:

- 2 x 6-Strand 50/125u multimode, Tight Buffered, Armoured, Laser Ultra-Fox Fiber cables
- Distance of run is approx 520 meters
- Total of 8 terminations (2 strands on each end of links)
- Testing, documentation

Thanks,
Hank

For that length, go with single-mode. 10G-LR will happily run on 10km of
SMF, but 10G-SR flakes out at ~300m even on OM3. Laying outdoor MMF plant
like this is totally pointless. Using MMF for anything outside your
cabinet / small cage is creating a legacy deployment on day 1 which will
bite you in future years.

To answer the question you asked: if the ducts are already in place and
you're just pulling fibre through, you should have a breakdown in terms of
# of terminations + the manpower required to handle the pull + cable
finishing. I.e. it shouldn't be very much. If you need ducting laid or if
your existing ducting is in poor shape, that's a different issue.

Nick

I had one 6-strand direct burial run through as-had 4-inch pvc between
two of my buildings about 4 years ago, IIRC, the final price was on the
order of $1300 for about a 300m run; terminated in ST boxes at each end
I don't recall if he furnished the patches or if we bought them ourselves;
I think the latter. They had to split the pipe halfway and put a pullbox
in/over.

What did they quote you?

PS: protip: split those 2+2 instead of 3+1 for better redundancy. :slight_smile:

Cheers,
-- jra

Second what Nick said. Also, get quotes for double, quadruple, and
more of the number of fibers you think you need today. If it makes
economic sense to leave strands unterminated (coil neatly in the
splice tray and have someone term later) by all means do it. Extra
strands in the cable are almost free compared to the labor to pull it
in.

-r

Nick Hilliard <nick@foobar.org> writes:

Where I work for a local telecommunications provider, we will not run any fiber smaller than 24 strand, and these days that is a drop into a building.

When talking about single mode fiber, the cost per foot difference in 2, 8, or even 24 strand is typically a matter of less than $1 per foot.
Some of the prices I've seen lately on google indicate about $.4/ft for 2-strand, $.5/ft for 6-strand, and $1.8/ft for 24-strand

It's all about the cost of getting it run by a contractor (which is typical if you have to get conduit installed, or run along telephone/power poles aerial) , unless you're in a position to do it yourself.

You'd likely have to pay someone to terminate it into a patch panel for you, but it may be cheaper for them to do all strands at once as opposed to having them come back later.

I second what Nick said. Single mode for anything longer than a few meters.

*IF* you have existing conduit, consider just buying an AMP Lightcrimp
Plus kit, picking up some single mode from ebay and doing it yourself.
Each Lightcrimp Plus termination is expensive so you wouldn't want to
use it for a large job or a large set of jobs, but they've reduced the
difficulty level to about what you're used to for RJ45. You could end
up in a break-even situation that leaves you with a tool set for next
time.

You can also buy pre-terminated fiber assembly with a pulling eye and
cable netting at one end for pulling it through the conduit. But
you'll probably have to go with new fiber; not much in the way of long
preterminated cables show up in the used market.

If you don't have conduit already, consider:

Conduit requires trenching and repair of surfaces afterwards. Big
dollars and God help you if you get an amateur because Home Depot
doesn't stock the right pipe.

Direct burial is cheaper for single installations but you have to keep
paying the whole price if you add to it later. Worse really, because
each new installation has to carefully avoid cutting the ones before.
Conduit, once installed, can support lots of additional cable.

Microduct is a happy medium between the two. It's about as easy to
install as direct burial cable and once installed you can both blow
new fiber through unused ducts and remove obsolete fiber from existing
ducts. Microduct even installs well across roadways with a machine
that looks like a four-foot circular saw. They can seal the road
overtop with tar instead of having to patch or repave which is a major
cost savings. Unlike conduit, microduct really only works for fiber.
If you also want to run some copper lines, you can't do it.

Regards,
Bill Herrin