Outside plant - prewire customer demarc preference

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1

Of course, every local carrier will be different, what are the current preferences for pre-wiring a customer demarc (NID, the box that hangs on the outside of the house, whatever the service provider calls it now)?

1. Nothing - telco/cable will do whatever the heck they want and wreck the outside of the house anyway

2. Smurf tube from demarc to central distribution point with an interior power outlet near the demarc

3. ANSI TIA-570 prewire (2 x CAT 6, 2 x RG 6) from demarc to central distribution point (low-voltage contractors don't use UV-rated cable for the demarc, and the jacket is trash in a few years)

In the past, I found if I made the pre-wire look nice and easy for the field technician, they usually made the extra effort to keep their work clean and tidy.

2

Of course, every local carrier will be different, what are the current preferences for pre-wiring a customer demarc (NID, the box that hangs on the outside of the house, whatever the service provider calls it now)?

1. Nothing - telco/cable will do whatever the heck they want and wreck the outside of the house anyway

This is pretty much the norm around me. If I can get with a builder prior to the walls getting closed up, I will hand them a spool I/O fiber for them to run from whatever they call the inside service point to the outside demarc for me, and they usually don't screw it up.

2. Smurf tube from demarc to central distribution point with an interior power outlet near the demarc

This certainly works well.

3. ANSI TIA-570 prewire (2 x CAT 6, 2 x RG 6) from demarc to central distribution point (low-voltage contractors don't use UV-rated cable for the demarc, and the jacket is trash in a few years)

This is almost pointless in the world of FTTH with indoor ONTs being preferred and even basically required for XGSPON (outdoor ONTs for XGSPON are uncommon and expensive). It'll make the local cable MSO happy, though, since they have RF ready to go. It'll make the local fiber provider scratch their heads and try to decide if it's worth using an outdoor ONT or just ignoring the pre-wire and starting from scratch.

This is doubly true of there's no outlet near the pre-wire outside the home. How the heck am I going to power my outdoor ONT to use that CAT6 without one? Reverse-power outdoor ONTs are even rarer and even more expensive.

In the past, I found if I made the pre-wire look nice and easy for the field technician, they usually made the extra effort to keep their work clean and tidy.

Most installations are contractors, and they get paid by the job with an add-on schedule that nobody's willing to pay for, so they're going to have a roughly set amount of effort they're willing to put into a job. If you've done 90% of the work for them, then that effort can be put into making it tidy. If they have to do everything from scratch, see your point (1).

Due to the use of indoor ONTs, lack of fiber pre-wire, and combined with customers wanting hand-holding up to and including managing their "in home WiFi", the "point of demarcation" has become really nebulous. In practice, the real demarc for many resi customers is their 802.11 SSID.

3

Around here, the local carrier seems to have stopped FTTH deployment. Instead, the carrier is convincing home builders not to spend money on demarc pre-wire. Wireless Home 5G service is all customers' need.

Of course, the lack of demarc planning makes things more expensive for
any post-construction competitor. And don't get me started about the lack of information of what's available in the utility easments. The builders don't know, and the service providers won't say. The FCC broadband maps are a lot of hand-waving by service providers.

4

Well, that's not going to end well.

Sadly, the circumstance in which we'll find out will be if SHTF, and after
that failure, it won't matter much.

Cheers,
-- jra

5

For *only* $1,000, the builder is willing to pre-install a smurf tube from the demarc to the central distribution point. But such a deal for 5G....

Since most fiber installs seem to use pre-connectorized cable, without affecting building structure integrity (i.e. 2-inch is too big according to builder), how small is too small? Trade size 1/2-inch, 3/4-inch, 1-inch?

Does the FTTH industry have any published standards?

This is why I don't help friends troubleshoot PC printer problems :slight_smile:

6

I can’t speak for US standards, however, in Australia on the National Broadband Network the standard for lead-in conduit is P20 conduit (23mm inner diameter with 26.6mm to 26.8mm outer diameter). I imagine in the US it may be something similar.

Page 17 of https://www.nbnco.com.au/content/dam/nbn/documents/developers/newdevs/NBN-DES-STD-0011-Residential-Preparation-and-Installation-Single-Dwelling-Units-and-Multi-Dwelling-Units-13.0.pdf.coredownload.pdf.

Regards,
Christopher Hawker

7

For *only* $1,000, the builder is willing to pre-install a smurf tube from the demarc to the central distribution point. But such a deal for 5G....

Yeah that's ridiculous. Running such a thing while the walls are still open is a piece of cake, and the material is maybe $50-100 depending on distance.

Since most fiber installs seem to use pre-connectorized cable, without affecting building structure integrity (i.e. 2-inch is too big according to builder), how small is too small? Trade size 1/2-inch, 3/4-inch, 1-inch?

Does the FTTH industry have any published standards?

At least my experience has been that, where pre-connectorized drop cables are used, they're only pre-termed on the telco side (often, but by no means always in a hardened connector). The customer side is either unterminated or uses a small ferrule with a snap-on housing precisely so that it can be fished through small holes in walls/framing and small or crowded conduits.

In practice, 1/2" trade size smurf tube is big enough if it's not too long and bendy especially if they're willing to get one with a pull-string already in it (and the guy before you is nice enough to pull another). If it's a long or bendy drop or you want a little extra piece of mind, 3/4" is readily available not too expensive. 1" starts to get a bit expensive and is usually unnecessary.

I personally connectorize both sides in the field. Having the ability to do it is invaluable for repairs, and it's not that much harder to do two sides than one especially if you're already fishing wires and such. If you're using hardened connectors, the situation is different since they're not commonly available for field install, though it is a thing you can get.

I'm not aware of any published standards focusing on FTTx in North America. All the standards I know of are datacenter/mid-size business oriented and are going to call for ridiculous (in FTTx) things like 2"+ rigid conduit on the assumption it'll have at least a 48F loose-tube in it and probably more than one.

I would imagine some of the national ogre telcos who are still doing FTTx deployments will have a pre-build guide for at least MDUs that might be useful, though around here they often just show up when the first person orders service and treat the building as "existing" even if it was just built last week. I'm guessing they have so many existing buildings to deal with at least right now that this isn't a huge deal for them and may even be easier than having two classes of MDU installs (existing and pre-wire). AT&T and Centurylink/Lumen are the most likely to have them IMO, but checking Frontier/Verizon (do they still have ANY wireline territory?) may be useful, too, especially since they were the earliest ones to do it.

8

Sorry long, detailed message.

TL;DR - Use 1-inch trade size smurf tube for new North America FTTH construction.

North American FTTH may not have standards for the in-building access conduit between the demarc point, Minimum Point of Entry (MPOE) in the old terminology, and the dwelling's distribution point. But thanks to Christopher Hawker for pointing me to other country's national broadband deployment guidance.

In the US, we don't even have a consistent word to describe that line on the network drawings. That line seems to be an "out of scope" gap between the the FCC demarc rules and TIA inside wiring standards.

Other countries with strong FTTH deployments have written a lot of rules about that line. Germany has extremely detailed FTTH building standards which influenced other European country FTTH standards. Carriers in several Middle East and other Commonwealth countries with national FTTH deployments have lots of documents for new builders.

Bear with me, because I'm going to translate nominal metric measurements and translate country-specific "pre-wire" rules using North American terms. Conduit, tube, pathway generally mean the same thing to me, but some people have been annoyed because their country uses different words.

Most FTTH countries specify a nominal 25mm I.D./32mm O.D. (equivalent to 1-inch US trade size) conduit/duct/pathway between the "dwelling" Distribution Point and the NID/demarc entrance point for new construction. In multi-dwelling unit buildings (i.e. apartments) the 25mm/32mm duct is between the apartment and a "consolidation point" for a group of apartments or the floor. Mansions (palaces) and other building types specify larger access conduit sizes. Countries vary a little, i.e. UK and Ireland have the smallest minimum access duct size (20mm I.D./25 mm O.D.) and some Middle Eastern countries have the largest (40mm ID/50 mm OD). Australia is just weird with a Telstra legacy conduit size.

Overall 25mm ID/32mm OD (equivalent 1-inch trade size) is the most common.

The biggest difference between country's FTTH rules are rigid vs. flexible conduit and the material specified, i.e. schedule 40 PVC vs. HDPE vs. other.

Also very confusing because the metric "Diametre nominel" size for pipes/conduit isn't the actual size of the conduits in metric measurements. 25mm is really 26.64mm inside diameter. Likewise the American National Pipe Standard isn't the actual measurement either. American 1-inch trade size is 1.029" inside diameter. The convention metric countries uses for 32mm outside diameter is really 33.40 mm.

Confused yet? Google translate does not help with construction codes.

The good news for North America construction, a 1-inch trade size HDPE/Schedule 40 PVC or smurf tube/duct/conduit/pathway requires drilling a 1-3/8 inch hole through framing studs. A 1-3/8 hole is just smaller than the maximum sized hole size allowed in a standard 2x4 framing stud (which isn't actually 2-inches by 4-inches) by North American building codes. So the builder does not need to charge extra to 'double' the framing studs for 'structural integrity' according to the building code.

Builder's scare quotes are intentional.

Insert NSFW construction joke here :slight_smile:

Mine (and my friend who will own the the new house) assumption is the builder's proposed $1,000 charge is really a "stop listening to your crazy friend, and let me build your house" charge.

9

Thanks Brandon Martin,

I agree 1-inch smurf tube is overkill for FTTH. From my quick research into all things FTTH, which I didn't know anything a week ago :slight_smile: ...

The regulators in other countries still believe they will create competition. The 25mm/32mm access duct (I'm going to make up a new term, and just call it "access duct", i.e. that smurf tube, conduit, pathway thing) is big enough for either a fiber microduct, cat 6 copper or RG6 coax. Even a 12/24/48-volt DC power cable for active equipment at the NID/demarc. The regulators keep all their competitors happy by not favoring any particular technology.

In practice, the countries with the biggest FTTH deployments have very little FTTH competition at the physical access layer.

Microduct, microduct, microduct is what the dominant access provider wants in those countries. The dominant carrier wants builders to install "direct fiber" or "bypass fiber" microducts in new construction directly from every dwelling (house or apartment) to the carrier's central access point for the builder's development (apartment buildings or neighborhood).

Microduct only means no pre-built access for other competitors.

Apartment construction in Asia is very large. Several countries are also adding in-building mobile/wireless service requirements for new MDU building construction.

My interpretation, not understanding the country-specific FTTH fights...

The regulators appear to say, Ok, dominant carrier - you can have "direct fiber" microduct but builders must also provide an "open competition" 25mm/32mm access duct from the building entrance point (NID) or apartment consolidation points (CP) to the individual distribution box (DD) inside each dwelling.

Just my uninformed take, corrections welcome.

10

If I was building a house I’d just get some 1" conduit from the outside to the inside. Put it in a NEMA box. That solves the problem forever.

As a fiber ISP, and assuming you’re doing your own WiFi in the house, you can do conduit inside or we can just run the fiber. We don’t want to run up/down walls and such. 99% of our installs are through the exterior wall and then a u6x covers the house. We run fiber

If you’re in a cableCo area just run coax to get to your modem/router situation.

I’m not sure what the Cat5 is for outside. Ethernet isn’t going to work and DSL is nearly dead already.

11

If I was building a house I'd just get some 1" conduit from the outside to the inside. Put it in a NEMA box. That solves the problem forever.

1" is great if you can get it, and I'd try to argue for it. I'd settle for 3/4"

Builders and resi electricians are going to hate 1". It's not something they'll stock nor is it readily available at cheeeap prices that they seek. 3/4" ENT is available fairly cheap, and the electricians are going to have a hole hog big enough for it which they may not have for 1" if they're truly resi-only. I can see the adder for 1" being eye-rolling as a result.

As a fiber ISP, and assuming you're doing your own WiFi in the house, you can do conduit inside or we can just run the fiber. We don't want to run up/down walls and such. 99% of our installs are through the exterior wall and then a u6x covers the house. We run fiber

Same. I don't expect to find a house pre-wired with suitable fiber from the outside utility access area to the inside distribution point. I'll use it if it's there, but the only time I've ever had that happen is when I've managed to hand the builder (or, more likely, the electrical contractor themselves) a spool of fiber during construction. Usually this is only on custom and semi-custom homes. Tract home electricians aren't going to do ANYTHING outside their SOW.

Most large fiber ISPs won't use existing fiber even if it's there and suitable. They don't trust it, and it's not "standard" for them. Occasionally the install techs may bend the rules.

When I'm running fiber for a customer, anything more than "rise up from the ground and poke it through the wall" is getting into "premium installation with upcharge" territory. Nobody wants to pay for it. Most other fiber ISPs seem similar.

If you're in a cableCo area just run coax to get to your modem/router situation.

Agreed. In theory they could also use suitable fiber for RFoG if they've got such a deployment in the area. I'm not aware of any standards for such prewires, and like above I doubt they'd want to use it even if it were present. All of the MSOs I know of doing RFoG to the home put a micro-nid outdoors and reverse power it over coax from inside. Fiber doesn't enter the home itself.

I'm not sure what the Cat5 is for outside. Ethernet isn't going to work and DSL is nearly dead already.

I suspect the relevant ANSI standard is just old and dates back to POTS+DSL. CAT6 is great for VDSL and G.FAST, and a standard cable gives you 4 pairs to work with and is cheap and fairly tolerant of abuse during install.

I would love to see the relevant standard updated to include e.g. a duplex or 6-count tight buffered or breakout single-mode fiber cable.

12

That’s exactly what I did. I was able to get a 3/4 conduit from my furnace room/network closet to the exterior of my home where utilities enter. It took some doing but I got it in, terminated in a NEMA box.

When we got fiber a few years ago, the installer told me it was the easiest install he’s ever done.

In that conduit I have fiber, coax, one Cat6 and also a sprinkler wire (whomever built my home had sprinklers put in the back yard but not the front, but I took care of that oversight).

13

Why would 1” be significantly harder to get than 3/4”? Both in EMT and PVC, it’s readily available to the best of my knowledge.

Owen

14

Most residential electrical contractors are going to use rated ENT since it's what they can easily get at a normal supply house or even home center. This is the stuff made popular by Carlon in their trademark blue that makes people call it "smurf tube". It's readily available in 1/2" and 3/4" everywhere from home centers to basically any supply house. 1" is less common - most home centers don't have it, and since it isn't normally needed in residential nor is ENT basically ever used in commercial, neither do a lot of strictly electrical supply houses.

You can of course get corrugated communication duct in that size, often with mule tape pre-installed as a bonus, but a lot of electrical supply houses that deal only in "electrical" and not "communications" don't have that and will send folks to a "low voltage communication supplier" or have to special order it. A lot of electrical contractors, especially residential, would rather not bother with a separate supply run, and having to wait is a pain if it wasn't planned early on and also often means you're paying freight separately.

Even then, most of the folks going to a communications supplier are going to reach straight for 1.25" or larger in commercial since you don't have to worry about drilling studs. As I recall, my local communication cable house didn't even have 1" in stock, but they did have 1.25" in stock, and their price was basically the same as the 1" as a result.

So it's not that it doesn't exist or anything, it's just that, at least as far as I've seen, there's not a ton of demand for it, so local stock is thin.

All that said, I just checked Home Depot, and they are showing some stock on 1" ENT at my local store, so maybe that's changing. Used to be they only stocked 3/4" and 1/2". They still only have 25ft hanks of the 1" stuff (you can get 1/2" and 3/4" in 25 or 100-200ft), but at least they have it now. It is still about 4x the price of 3/4" per unit length, though.

15

Why not just use SCH40 PVC sticks? Everywhere stocks that in copious levels.

16

Because in my instance, due to some of the bends involved, 3/4 was the best I could do. The bend radius on a 90 for 1-inch wasn’t going to fit in a couple places along the path.

-Andy

17

Why would 1” be significantly harder to get than 3/4”? Both in EMT and PVC, it’s readily available to the best of my knowledge.

Most residential electrical contractors are going to use rated ENT since it's what they can easily get at a normal supply house or even home center. This is the stuff made popular by Carlon in their trademark blue that makes people call it "smurf tube". It's readily available in 1/2" and 3/4" everywhere from home centers to basically any supply house. 1" is less common - most home centers don't have it, and since it isn't normally needed in residential nor is ENT basically ever used in commercial, neither do a lot of strictly electrical supply houses.

I’ve never used ENT (never even seen that name, TBH). 1” EMT is readily available at Home Depot and Lowes out here as well as several reputable supply houses.

You can of course get corrugated communication duct in that size, often with mule tape pre-installed as a bonus, but a lot of electrical supply houses that deal only in "electrical" and not "communications" don't have that and will send folks to a "low voltage communication supplier" or have to special order it. A lot of electrical contractors, especially residential, would rather not bother with a separate supply run, and having to wait is a pain if it wasn't planned early on and also often means you're paying freight separately.

Agreed, but out here at least, almost all of the electricians don’t bother with ENT and most do both commercial and residential work, so they just keep EMT on the trucks and usually have up to 2” readily available, with 3” and 4” in the not particularly difficult, but too bulky to carry unless needed category. I guess this may vary with locality.

Even then, most of the folks going to a communications supplier are going to reach straight for 1.25" or larger in commercial since you don't have to worry about drilling studs. As I recall, my local communication cable house didn't even have 1" in stock, but they did have 1.25" in stock, and their price was basically the same as the 1" as a result.

Sure, but smurf tubing is a hole other thing. Amusingly, at least locally, smooth interduct is easier to find than corrugated smurf tubing, though both are readily available.

So it's not that it doesn't exist or anything, it's just that, at least as far as I've seen, there's not a ton of demand for it, so local stock is thin.

I guess this varies by locality.

All that said, I just checked Home Depot, and they are showing some stock on 1" ENT at my local store, so maybe that's changing. Used to be they only stocked 3/4" and 1/2". They still only have 25ft hanks of the 1" stuff (you can get 1/2" and 3/4" in 25 or 100-200ft), but at least they have it now. It is still about 4x the price of 3/4" per unit length, though.

Interesting… ENT is apparently plastic and has interesting snap fittings. Until this email, I’ve never even looked into it. Used plenty of the “ENT” boxes, but always just called them PVC (since that’s what the ENT stuff is apparently made of). EMT is way more common out here than ENT, and even where plastic is used, most seem to use straight electrical PVC (grey stuff usually) instead of of the ENT brand stuff.

YMMV of course.

Owne

18

My relative is buying a new house is a typical American surbuban tract housing development. Yep, I'm the extended family I.T. consultant.

The marketing brochure calls it "custom home" but he only gets to talk to the developer's "design consultants", i.e. sales people. The developer has a sales center and pre-set upsell options, kitchen countertop choices, carpeting, etc. He never talks to the architect, general contractor, electricians or construction crew.

He paid for a finished basement option, which means most of the basement will have sheetrock finished walls. So the first cable, fiber or telephone utility will be cutting holes in the new sheetrock. I was trying to avoid needing to cut brand-new sheetrock or fishing wire through walls.

The design consultant's answer for everything was 5G ... 5G ... 5G. No more ugly boxes on the house, everything will be wireless. There is a special deal if he signed up for 5G wireless service before his house was finished.

For something "no one ever asks about," the design consultant seemed to have a lot of prepared sales pitches.

Acting like a dumb homebuyer over the Thanksgiving weekend I did notice the model home had a demarc box on the garage outside wall. The garage in the model home is used as the builder's office, so it may not be how the built homes are setup.

A new version of ANSI/TIA-570 (residential wiring standard) is due this year. In the old days, a minimum of one wired telephone outlet was required. I was just wondering if there was new 'standard' for demarcs in new residential construction. But it sounds like there isn't. Draping cables around the sides of the house.

19

I am not personally aware of such a standard that is used in every state, but it is worth checking with the state authority to see what standards are applicable in the state.

That being said, I would ask if the home is being prewired for alarm services or not. If so, you could find an avenue to ask about other things. My sister and her husband just bought a new house outside of Dallas and it is coming prewired for RG6, wired alarm and CAT-6 ethernet.

20

Thanks for the suggestion. I suspect the builder will try to sell a wireless alarm system instead, but I will suggest my relative ask the design consultants.

During my "dumb homebuyer" Thanksgiving tour, I found out the $1,000 smurf tube option was a 5-foot tube (2-inch) from the TV mounting box above the fireplace mantel to the side of the fireplace for a media console for a hdmi cable.

On the other hand, the sales person was very proud that the garage is "EV-Ready." Which is how I found out the garage was their office, not on the tour.