Is installing data cable conduits impossible?

[YorkieSelfBuild]

Hi, how difficult is it to install conduits to feed ethernet cables through?

 

It's a new self build house, no internal walls yet so I thought it's a no brainer to get it right now to make it easier to replace damaged or upgrade cables in future.

 

My builder says it wouldn't work going through floors, corners, studs and joists. It's too cramped and they've failed to pull cables in other residential projects. A data cabling installer said you can't pull round corners or angle boxes so you'd need to cut into floors and walls to access them.

 

Are they right?

[ToughButterCup]

18 minutes ago, YorkieSelfBuild said:

...

It's a new self build house, no internal walls yet so I thought it's a no brainer to

...

 

Upstairs flooring laid yet? 

Downstairs ceilings in yet?

 

A (Several) photo(s) of the problem would help us help you more quickly

[ProDave]

You can get swept bends for conduit which will work

 

https://www.ebay.co.uk/itm/145467409061?

 

Secure the conduit runs well, you don't want it coming apart if trying to fish a wire down later when it is inaccessible.  Consider solvent welding the fittings to make sure.

[JohnnyB]

If you have large enough conduit and a draw cord I would put something in. I have 50mm dia running from ground floor to attic and that was easy to get twin & earth through without a draw cord.

If you can break it down into smaller runs it would be easier to pull it through in the future as well.

 

If you can actually lay the cable you need at this stage it wil be easier, but for future proofing if you plan out the runs and how it can be accessed it there are issues, avoiding tight spots etc. having conduit must be easier than nothing at all.

[ProDave]

One thing I did for possible future runs, is in all the upstairs rooms I put a half board removable section of floor board at each end of the room, so 300mm wide, only screwed down and tongue or groove modified so it can be lifted.  This will give access to the posi joist ends and allow additional cables to be pulled through around the room.

 

Your spare conduits could be fitted in the walls as straight runs terminating in this accessible under floor space.

[BotusBuild]

I've put conduits in to run extra cables from plant room on ground floor to roof level for things like solar and aerial cabling. All have draw chords ready to pull cable

[YorkieSelfBuild]

5 hours ago, ToughButterCup said:

 

Upstairs flooring laid yet? 

Downstairs ceilings in yet?

 

A (Several) photo(s) of the problem would help us help you more quickly

No flooring or ceilings finished, or even interval walls. Still shell stage.

[YorkieSelfBuild]

Builder says maximum 25mm conduits in floor and wall voids. Their previous experience is it's hard even from road to house with 40mm semi rigid ducting, with draw cord getting stuck.

 

I'll have to ask if they've tried it inside the house. I gather he's only using a sparky, not cabling engineer, so maybe not very experienced.

[BotusBuild]

If just a shell then install as much cabling as you can, and then conduits with draw strings with long radius bends wherever you think you might need cables in future.

 

However, just pull as much cable as you can now, even if you don't use it  straight away. Just keep lots of notes/photos of where the cables end

[YorkieSelfBuild]

5 hours ago, ProDave said:

You can get swept bends for conduit which will work

 

https://www.ebay.co.uk/itm/145467409061?

 

Secure the conduit runs well, you don't want it coming apart if trying to fish a wire down later when it is inaccessible.  Consider solvent welding the fittings to make sure.

Yeah, someone suggested Tufflex elsewhere. A lot more expensive than flexible ENT tubing I was thinking of

[BotusBuild]

Is the 25mm a physical space limit? I find that very difficult to believe

[YorkieSelfBuild]

4 hours ago, ProDave said:

One thing I did for possible future runs, is in all the upstairs rooms I put a half board removable section of floor board at each end of the room, so 300mm wide, only screwed down and tongue or groove modified so it can be lifted.  This will give access to the posi joist ends and allow additional cables to be pulled through around the room.

 

Your spare conduits could be fitted in the walls as straight runs terminating in this accessible under floor space.

That won't work as I'm planning glue down LVT upstairs and tiles downstairs.

 

Could I add access ports in plasterboard walls instead?

[BotusBuild]

2 minutes ago, YorkieSelfBuild said:

Could I add access ports in plasterboard walls instead?

Yes. Up to you how visible they are

[YorkieSelfBuild]

5 hours ago, JohnnyB said:

If you have large enough conduit and a draw cord I would put something in. I have 50mm dia running from ground floor to attic and that was easy to get twin & earth through without a draw cord.

If you can break it down into smaller runs it would be easier to pull it through in the future as well.

 

If you can actually lay the cable you need at this stage it wil be easier, but for future proofing if you plan out the runs and how it can be accessed it there are issues, avoiding tight spots etc. having conduit must be easier than nothing at all.

Did you use flexible or rigid tubing?

 

I'm limited to only 25mm max. I was thinking of flexible ENT tubing unless rigid is better?

[mads]

6 minutes ago, YorkieSelfBuild said:

Did you use flexible or rigid tubing?

 

I'm limited to only 25mm max. I was thinking of flexible ENT tubing unless rigid is better?

As others have said, where is the 25mm max limit coming from?

 

Re: ENT tubing, it is cheap but it is not smooth internally so could find pulling cables more tricky as can snag. I am having posi joists fitted which will allow larger conduits run and will fit smooth inner to prevent snagging.

[garrymartin]

@BotusBuild is spot on - pull as much as you can to wherever you think you might need it.

 

By all means use conduit now if you want to protect the cabling whilst you are still building, but don't expect to be able to easily pull anything through in the future, especially if there are already cables in it or you don't have a straight run. There's a reason data cabling professionals use cable trays... 😉

 

By all means, use conduits for things like vertical risers (but not 25mm), but you'll struggle to go around any corners unless you have wide swept bends, and the more corners you introduce into a run, the more changes in direction, the more difficult it becomes.

[MrSniff]

Conduit is used as a matter of course here (Luxembourg) in newish builds, usually flexible ridged plastic. Theoretically this means bends are swept, but the ridges make pulling cables more difficult than you would think - as evidenced by a less than enjoyable and somewhat blue air day removing a coax cable and pulling through new double barrel cable across two floors…

[BotusBuild]

1 hour ago, MrSniff said:

blue air day

Ahh, blue air days. Had a few of those pulling cables in my early work life

[JohnnyB]

3 hours ago, YorkieSelfBuild said:

Did you use flexible or rigid tubing?

 

I'm limited to only 25mm max. I was thinking of flexible ENT tubing unless rigid is better?

I tried flexible outside and it was nearly impossible to get one ethernet cable through anywhere it wasn't straight so I have only used it to protect cables underground where the cable was pre-pulled through. I wouldn't buy it again but used it as I have already got it.

From downstairs to Loft I used 50mm external conduit that is semiflexible and smooth inside. That was easy to get several T&E cables through.

I have used 25mm rigid from the ceiling void down to sockets with a draw cord and that was fairly easy to pull cables 2x 2.5mm T&E through, but they are short runs and most bends were bend using a pipe bender for copper pipe which gives long bends.

From inside to outside I tried 25mm rigid with glued in bends and it was hard work to pull 2 ethernet cables through where I had 2 bends fairly close together.

 

Try to use a bigger internal diameter and make sure it is smooth, and as everyone says you want long bends, or use a pipe bender on the rigid lengths and join lengths together where you have straight runs.

[MikeSharp01]

If you are going to do this with conduit you are best advised to put in a draw string. I have used plastic builders brick line, it is amazingly strong, does not stretch, wont rot and is very thin here and have only had one issue where I was trying to pull 2x 10mm²  cables through 20mm conduit. As you pull a cable through with it you can pull in more string and it makes it so easy as does a bit of cable lube. 

[Alan Ambrose]

There are three other techniques that may help in tricky circumstances - one is judicious use of small hubs to avoid running parallel cables over any distance- powered by PoE if possible. The other is use of ethernet splitters - in some circumstances (non-PoE I believe) you can ‘get two lan connections down one cat5’. Lastly vlans might help in some instances when you want two logically separate networks ‘down one cable’. The internet was designed to offer a bunch of flexibility…without running vast quantities of point-to-point cables everywhere.

[YorkieSelfBuild]

So I had a chat about conduits with the builder and he's suggested some conduits but only straight sections and having some end underneath floors for future use. I'm not completely sure what he meant, might ask for a layout drawing, as still need to decide where the ethernet ports should go.

 

I might have to settle for that due to budget and time constraints as 1st fix is starting soon. I guess some conduits is better than nothing

[Mike]

I'd suggest 25mm minimum diameter flexible conduit, with a draw cord + gentle bends, but as straight as possible. Here in France that's commonly used for single cables Cat 6 / 6A cables - I hope so as it's what I've installed. Despite being against the standards, I've heard that it's possible to pull a pair of them through.

[Galileo]

Thinking about the number of cables I've squashed into a 25mm trunking, I'm wondering what your builder is going on about. Admittedly, I work in IT, so maybe I'm a bit more relaxed about how things get cabled* when doing it myself, but not had a failure in 30 years. The only rule is to try and keep 50mm from any mains cable, but then I'm trying to maintain high speeds, would imagine a smart TV or home PC plugged into an Ethernet port is going to be less worried about losing a bit of that 1000MBit max for good old-fashioned CAT5E. Considering the price of a 305m box of CAT5E LS0H is less than a decent meal out for 2, just pull the cables in.

 

*I'm a bit more rigid with a new office and in a meeting with the M&E people, trays, radius, separation, CAT6. fibre runs etc.