Im putting some ducting underneath my floor boards so that Virgin media can run a cable easily to the location I want it installed for TV & Internet.
My question is how large does the ducting need to be?
Can the connectors be added on after the cable is ran through or are the ends already attached. Just tested the ducting with some existing cable for size and the end pieces don’t fit through the ducting but the cable will.
thank you
What are you planning to put into the ducting? Just the VM cable or other audio visual/networking cables as well?
A VM tech would install coax cable to the required length and add connectors to the cable. For fibre optic cables I think VM uses ready-made leads with the plugs already attached.
The largest diameter conduit you might get locally and easily off the shelf will be 25mm. That should certainly be able to take a single VM cable even with connectors fitted.
You may find difficulties increase if you have corners and bends in the conduit. If you are making a simple and relatively straight run you could use a continuous length of 25mm flexible conduit. If it is going under a floor, make sure it is well fixed to avoid the conduit being dragged about when the cable is pulled through. Avoid any sharp turns in the conduit. The longer the length of duct the greater the difficulty may be to pull the cable through. Fit a pull rope for the VM tech to attach the cable to.
Cable lubricant can help pull cables through ducts
https://www.screwfix.com/p/ideal-yellow-77-wire-cable-pulling-lubricant-950ml/44462
goes on as a liquid and dries to a film.
Thank you. It’s a 5m straight run so should be simple enough. Not sure your questions regarding the cables. I have a box on the outside of the house that an engineer will tap into. Already have existing cables running to different parts of the house. The cable that needs running through the conduit is for Virgin media tv and internet so whatever that is. I’ve bought 16mm internal diameter conduit which fits the cable thickness but not the connecting coax piece hence my inquiry. Don’t want to install it under the floor boards only for the engineer say it’s too small. I also want the conduit to be as small as possible as it then has to rise behind some skirting boards.
From your initial post, I had assumed you were a new customer getting TV/BB.
If VM is simply putting in an extra cable for you to a new location, the norm would be that the tech will pull through the required length of cable and terminate the ends for you with a connector on each end.
Conduit is normally described by its external diameter. 20mm (with an internal diameter of 16 or 17mm) and 25mm is readily available for DIY use. Presumably you have bought 20mm conduit.
The VM tech should be able to pull a piece of standard coax cable (approx 7mm diameter) through 20mm conduit without issue over a 5m straight run if you fit a suitable pull rope.
A draw wire is the most suitable tool for this, which can be reused
https://www.toolstation.com/draw-tape-nylon/p35379
Thanks again. I bought two sizes of conduit and based on your answer I’ll risk the smaller one I bought which has an internal diameter of 13mm. The cable fits, it was just the end connector I was concerned about.
I am not familiar with electrical conduit that is as small as 13mm ID. For clarity, 'conduit' has a round cross section (a tube). Other alternatives such as hose pipe, drain pipes etc. are generally not suitable for pulling cable through.
'Trunking' may go down to 13mm sizes. It has a square or rectangular cross section and has a clip-on lid. Personally I would not use trunking under a floor when trying to pull cable through. It is designed to be fitted on a flat surface, then cables fitted inside and the lid clipped on afterwards.
If I was doing your task I would fit a continuous piece of 20mm outer diameter flexible electrical conduit under the floor and make sure it was well-clipped along the route (which prevents the conduit moving when the cable is pulled through). 20mm electrical conduit is also compatible with generic electrical fittings, such as electrical back boxes. With a draw wire in place, the VM tech should not have any problems pulling a single piece of coax cable through 20mm conduit over a 5m straight run.
It’s probably not electrical conduit tubing. It’s corrugated flexible conduit. I need it to be flexible to come up and through some skirting board.
its a 5m straight ish run underneath my floor boards then will bend upwards towards skirting board. I was hoping the one of the two diameters I have would be sufficient based on whether the cable end can be connected afterwards.
