Drilling holes in the right places on front wall of house - am I over-thinking this?

[AVR2]

I want to put Ethernet sockets in my living room and in the bedroom directly above, connected by a cable that will run up the front exterior wall of the house. See the photo below (not my house) for how I'd like the cable to be positioned relative to the windows.

I want both sockets to sit just above the skirting board (proud, not chased in), and for the cable entry to be directly behind them, so no cable is actually visible inside the room. I also want the external cable run to be exactly vertical, with no diagonal slope or direction changes, so obviously both holes in the wall need to be exactly in line with each other.

If I drill the upstairs hole first, I can obviously mark up the internal side of the wall exactly how I want it and then use a plumb line outside to get the correct line on which to drill the downstairs hole - but how do I get the downstairs hole the correct height off the ground for the internal socket to be sitting in the right place just above the skirting board?

Do I just have to take measurements indoors using common reference points, like the edges of the windows, and then transfer those to the external side of the wall?

Logic says yes, that's the only way, but I thought I'd check, just in case there's some special builders' technique...

 

[SFK]

AVR2,
All sounds good - but one big issue (in my opinion).
If you run the cable straight down the wall and then straight into the house (so it looks like a big staple on cross section), then rain water can collect and run down the entire length of cable and then some of the water will follow the cable route into the house.

So normally I put a loop in the cable below the lower ingress point.
Make the cable slighly longer, make it pass the ingress point, a 180 deg loop, and back up to the hole.
Teh water then drops off the lower point of the loop.

As this loop has to have a diameter of say 50mm (so does not damage cable), this means you can be a bit more forgivving about the location of teh lower hole.
It also gives you some slack in the cable that you can use now and later when you are conencted the cable to teh internal sockets.

Images of drip loops
https://www.google.com/search?q=drip+loop+in+cable

SFK

 

[Harry Bloomfield]

Cables draped down outside walls and run surface inside are a pet hate of mine, might it not be better to find an alternative route so the cable is hidden? What route do your central heating pipes take between the ground floor and upper floor?

 

[Munroast]

I doubt the OP is being serious - nobody would trash their own house in this manner and then worry that the cable was not plumb.

 

[AVR2]

I doubt the OP is being serious - nobody would trash their own house in this manner and then worry that the cable was not plumb.

That's extremely condescending, as I'm sure you're aware.

I'm completely serious. I want to extend the downstairs wired network upstairs, and there are no existing conduits I could run cable through.

Cables along exterior walls are a completely normal and accepted part of the urban landscape - ask anyone with a Sky installation. Indeed, my Ethernet cable will be running more-or-less alongside my existing Sky cable and my direct-to-home fibre, both of which run vertically down the front wall and don't particularly stand out. And the closer to plumb a cable is, the less it catches the eye; it's able to merge into the natural horizontal and vertical lines created by the brickwork, drainpipes and so on, in a way that cables run along a diagonal don't.

SFK - many thanks for that, very useful advice.

 

[SFK]

My pleasure.
Note that I also hate cables down walls of houses - and you have great looking brick work. .
I have hidden them behind Guttering down pipes.
But some times no other solution.
SFK

 

[Munroast]

That's extremely condescending, as I'm sure you're aware.

I'm completely serious. I want to extend the downstairs wired network upstairs, and there are no existing conduits I could run cable through.

considering it is such a beautiful front elevation. - sacrilegiousium

How about wireless - I have an old router upstairs that the main internet router downstairs talks to, I can then run an Ethernet cable from the old router to, for instance my old printer (that is kept in a cupboard in an unused room) that is not a wireless printer.

Other options can use the wiring in your home electrics. The ethernet cable plugs into a device plugged into a 3 pin socket, you can then plug another ethernet cable into any other socket in the house to complete the 'wired' network