Pulling new coaxial through with old cable stupid?

Is it always a bad idea to pull the new coaxial cable through by attaching to the end of the old one and pulling?

It's a plasterboard house, with the coaxial starting from loft down to lounge.
I don't really want to hack through the plasterboard, but I'd rather this than run cable outside.

It may or may not be fixed in place behind the plasterboard.
If it is loose and a new cable can be pulled through, is there the chance of the cable rubbing and getting damaged over time or even it touching an electrical wire or metal pipe and getting interference?

Hi James,

pulling cable through plaster is quite normal although the route is usually done on a best educated guess of the person doing it. (bearing in mind safe cabling zones)

I often use old cables to pull new ones through where possible, also cutinery wire, drain rods & the like, the latter two being better as there not likely to split half way through a pull.

there are pitfalls though of pulling wire, regardless of which method you use & thats where the educated guess comes in. Hot water pipes, heating pipes will damage the coax over time, pulling them like that means you can't see if they cross over mains wires, likewise if they snag half way through, you don't know what on or if it damages the cable.

the answers to these though are easier if your replacing an existing cable using the same route, as it would hopefully have worked at some point. you can also inspect the cable you remove to see if there are any burn marks, kinks / warping from heat pipes etc.

most cable has a rating for being pulled, you should be able to google the cable you've bought & see what the max stress it will take is.

you can also look on the walls following the route to see if there are any appliances / sockets etc & maybe try an alternative route.

maplins sell cheapy drain rods for about £6-£7. screwfix sell some better ones £15 - £70

By saying "plasterboard house" I assume you are talking about dot and dabbed dry lining on the outer walls rather than simply talking about stud partitions.

In either case, the old cable could be clipped. It almost certainly will be either clipped or run in capping/tube on the dot and dabbed walls.

You may be able to pull through, you may not. There is no simple answer to this.

Why are you replacing the cable?

I personally dont fancy your chances sorry. If the coax is in a timer framed house or down a stud wall I would have expected it to be clipped at 1st fix. If it is in conduit and a solid wall you have a better chance. Do you live in a house if so there is a good chance that it is not a straight run to the loft. Sorry for the downbeat info.

..

It's a house built in 1990. dot and dab.
The cable looks like it's the original cable from when the house was built.

It's just a case of renewing the existing cable along the same route, with some decent quality cable.

I'll have to investigate more, and try testing the signal connected directly to the aerial with my tv carried upstairs.

The cable dissapears at the point in the loft directly above the tv socket.
My guess is that is goes straight down unclipped behind the plasterboard in the bedroom and then lounge (if the way other things have been done in the house is anything to go by).

I'm going to be paying a company to move my aerial from loft to roof, and I just don't like the idea of them running cable down my house or drilling through the wall near the ground to connect to my lounge socket.

if your paying to have the aeriel moved, then usually they will as you say, supply & fit a new cable too.

most engineers will run the cable in the route you request, however time more than how much of a roll of £6 RG6 cable is used is normally the factor,

I would check & see if you can pull the original cable first, maybe tape some strong industrial type string (the blue stuff) used for pulling wires through ducting and leave that there for them.

"if" its as simple as them taping there wire to your string & you've confirmed already that it can be easily pulled, then they should happily do that..

or while the engineer is there, you could both pull the new wire through before he cuts a length off the roll...

There are special cable lub like yellow 77 that will help but I would think your chances are slim.

I would use a loft box to both boost and give power if required for any mast head boosters then problem found today is the digital signals unlike old analogue are spread all over the band and this means you need a wide band aerial. These are much larger than the old narrow band types and to keep the amount of metal in the air down to reduce possible wind damage one often has to resort to amplifiers. The closer to aerial the better they work. So mast head ones are considered best.

I assume before going to expense of moving aerial you have already tried one? There is of course nothing to stop you using a mast head amplifier in the loft this is often done where there is no power in the loft as with mast head amplifiers the power is sent up the same coax as signal comes down and you use a power supply down stairs which does this.

You do need power in loft for loft box but these use a single cable for multi signals and allow you to watch same TV signals in bed rooms.