What size hole for Ethernet through cavity wall? Ducting?

I'm currently using a pair of Powerline adapters to get connectivity from my home's router, at the Open Reach master socket at the front wall of the house, to an extender at the back wall of the house, for internet TV and Wi-Fi at the rear of the property.

I'm considering replacing the Powerline link with a wired Ethernet connection, using a couple of surface-mounted single-port sockets, and cabling through the cavity walls to run externally around the house to the other side. I'm hoping to get lower latency, faster throughput and have fewer electrical devices running.

Should I use some kind of ducting to carry the cabling through the walls and across the cavity? I'm presuming that Cat6 external Ethernet cable is about 6mm diameter (that's what it says on the Amazon-listed extension kit), so perhaps I need a plastic tube with an 8mm internal diameter to protect the cabling as it passes through the wall, implying an external diameter of about 10mm.

Does this sound like the right approach?

If so, can I really drill a 10mm hole through masonry without owning an SDS drill? I only have a keyed-chuck consumer hammer drill.

Any thoughts and experience welcome.

You are on the right lines. Conduit is not essential across the cavity, but it could help to run the cable in the first place - once it is in place, the conduit serves no great purpose other than to partially fill the hole you made.

When it comes to drilling the hole, you would be limited by the smallest diameter drill bit you could obtain with the length you need. Plus you would do well to use a shorter drill of the same diameter to break through the first leaf rather than start a hole with a 400mm long drill. SDS is not essential, a key chuck consumer hammer drill will do the job. [But bear in mind that one famous brand designed their consumer grade drills with a service life of 30 minutes!].

When it comes to running the cable, best to lay it down outside, cut the required length and poke each end into the house rather than drag the full length in from outside. This avoids abrasion of the whole length You don't need conduit to bridge the gap, you can poke though a length of copper stripped from some 2.5 Twin and Earth and use that to pull the cable through. Having said that, you might find that the smallest drill bit you can use is big enough for conduit.

do you have access to the roof ? Because i'd go up, across and then down. As i've needed speed i've gone the fibre route and then convert to rj45 i where i need to.

In reply to a post by East_Anglian:

I'm currently using a pair of Powerline adapters to get connectivity from my home's router, at the Open Reach master socket at the front wall of the house, to an extender at the back wall of the house, for internet TV and Wi-Fi at the rear of the property.

snip

Should I use some kind of ducting to carry the cabling through the walls and across the cavity? I'm presuming that Cat6 external Ethernet cable is about 6mm diameter (that's what it says on the Amazon-listed extension kit), so perhaps I need a plastic tube with an 8mm internal diameter to protect the cabling as it passes through the wall, implying an external diameter of about 10mm.

I put Cat 5e through the wall without ducting a few years ago without any issues.

In reply to a post by East_Anglian:

<snip> and cabling through the cavity walls to run externally around the house <snip>

One important thing to note is, when drilling from inside to out, make sure the slope of the drill is slightly downwards. This should stop water penetration from running along the "cable bridge" between the cavity. The other point is to have a drip loop on the outside where the cable exits the wall, again to stop water running into the property. It is amazing how many ISP installers don't use a drip loop and just plaster everything with silicone sealer.

In reply to a post by Adduxi:

In reply to a post by East_Anglian:

<snip> and cabling through the cavity walls to run externally around the house <snip>

One important thing to note is, when drilling from inside to out, make sure the slope of the drill is slightly downwards. This should stop water penetration from running along the "cable bridge" between the cavity. The other point is to have a drip loop on the outside where the cable exits the wall, again to stop water running into the property. It is amazing how many ISP installers don't use a drip loop and just plaster everything with silicone sealer.

The other point about drilling from inside to out is to drill a pilot hole first, to minimise the damage to external bricks. The City Fibre installer who installed my current ONT did this, and the result is much tidier than that previously undertaken by Kelly's, on behalf of City Fibre.