This topic

Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 00:15:54 GMT

Hello guys

We cant talk to open reach and my exisiting ISP is Virgin who dont either > want to switch

To be clear My router needs to be in a location other than where cable enters the house ( connects to ethernet patch panel )

While open reach were in my area kindly engineer gave me a suitable length of their fibre cable . I ran it under the floorboards in my house to future proof . LOL that time is now

QUESTION Will BT /openreach be happy to join to this completely unterminated cable on the day of switching

( from cable they run in from the road) And of course terminate the other end

It is easily accessible at either end and lots of it.

Cable ID

"Dexgreen inside/out IFO G657B3 LSZH outer CPR B2ca (s1a d0 a1) UV"

cant send photo too big size But picture y'self A.N.Other ISP cable entering house ( mine is currently coax ( virgin) Now that cable joins to another under floorboard coax cable to router in other place Alongside in the house is the black fibre cable unused and waiting.

Can anyone say if joining to this cable will be a problem for installers. Dont want to dig up the floor boards. Wish to all go smoothly on changeover day

Understand this is a open reach priority area if that helps

thanks

Re: Cab BT connect to existing open reach fibre cable ?

iniltous — Fri, 30 Jan 2026 09:29:55 GMT

Generally Openreach will not use anything you supply because they then have to take responsibility for its maintenance…..some people have success by providing their own cable containment ( duct for example) with a draw cord , the ‘duct’ running from where the customer suspects the external cable will appear at their property, to where they want the ONT located , the engineer then simply uses the draw cord to pull the Openreach ‘internal’ cable into place …it’s not guaranteed, and obviously this duct or whatever needs to be usable, no tight bends etc .

As far as your router location , you can always run your own Ethernet cable to anywhere you like from the ONT , the ONT position needs the Openreach installers agreement , the other end of your own Ethernet cable is your choice , it’s only if you want the ONT in a specific location and that would require an unreasonable amount of work to get the cable to that location you need to do some mitigation work yourself….but as stated no guarantee, you may do lots of preparation and the installer still says ‘No , it’s not suitable’ .

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 14:32:06 GMT

Hello iniltius ( Royal Navy ?)

thank you for that . Ok its luck of the day at best probably unlikely without floor board up. Seems dog in the manger but hey

Could you just advise Is it actually possible for them join this kind of fibre cable ? I had it they do this all the time ? dont they have to terminate one end anyway after pulled into the house ?

help with option Ethernet connection if you would : Would that terminate in the router ethernet port ? Then out to my patch panel ? The other end goes where Whats the geography

forgive not tech savvy with this.

perhaps I'll just stay with Virgin But sitting duck for their charges.

thanks again for you reply Ms O

Re: Cab BT connect to existing open reach fibre cable ?

licquorice — Fri, 30 Jan 2026 14:38:46 GMT

External fibre > CSP ( customer splice point) > internal fibre > ONT (optical modem) > router WAN (port 4 on BT Smart Hub2) how it gets from ONT to router is immaterial.

Re: Cab BT connect to existing open reach fibre cable ?

chrisjp — Fri, 30 Jan 2026 14:50:14 GMT

Openreach usually want to put the customer splice point on an external wall, as near as possible to the internal wall location of the ONT. So they are unlikely to want to use a length of optical cable that is running under floorboards.
But, as has been commented, it's no problem, just connect the ONT to your hub/router with as long a length of ethernet cable as you need.

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 17:11:58 GMT

Hello Liquorice

thank you/ again forgive dummy: whats an ONT ?? googling as fast as I can but possible misunderstanding

Is it this "ONT optical box" would still require a physical ethernet cable to be run to " other location of house patch panel ( across the hall under the stairs actually ) which puts me practically back to under floorboards ?

still seems the only practical solution is forget the house patch ethernet just let open reach drill a hole through the wall plonk the router there use wifi ? Isnt that what they usually do Do assure many of my neighbors are on BT fibre there is no problem with fibre cable coming to the house

thank you again : trying to keep fingers crossed but still looks like open floorboards or give up

ms\o

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 17:20:53 GMT

thank you

see my reply to your colleague

looks to me its open the floorboards or give up on the house ethernet network ..

stil like a definitive answer to " do open reach installers routinely join these fibre cables without second thought ? "

Kit is in the van ?

Then thinking if I left a cup of tea and biscuits with the open reach guy and a small brown envelope there could be an accidental loint made to the cable

or stick with virgin .. They happily join their co ax.

Re: Cab BT connect to existing open reach fibre cable ?

licquorice — Fri, 30 Jan 2026 17:26:37 GMT

As stated in brackets, the ONT is the optical modem to convert the fibre to Ethernet which is then connected to the router. The fibre doesn't go to the router.

The ONT and router don't need to be co-located, they can be up to 100 metres apart connected via Ethernet.

Just use your fibre cable to pull an Ethernet cable through.

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 17:30:29 GMT

sorry again . bear with . so are you saying I dont need a physical ethernet cable from ONT to router Its an optical connection
Is that what some folks do if they want a router somewhere else other than point of entry to house ? Id need support on that
recommend me one ?

Re: Cab BT connect to existing open reach fibre cable ?

licquorice — Fri, 30 Jan 2026 17:34:16 GMT

No, you are not reading what I am saying. It is the opposite, the connection from ONT to router is Ethernet. Therefore your cable is not required and can be replaced by an Ethernet cable.

Re: Cab BT connect to existing open reach fibre cable ?

iniltous — Fri, 30 Jan 2026 17:44:46 GMT

No , you do need an Ethernet cable connecting the ONT to the router , the point is a standard Openreach installation the router and ONT are connected together with a very short Ethernet cable ( so they are co-located in the same room ) , if you want to supply your own much longer Ethernet cable so you can have the router much further away from the ONT , you install the ‘long’ Ethernet cable yourself , underfloors , through walls , whatever you want , as you will be doing the work to install this longer Ethernet cable yourself, (not Openreach) , you get the cable in ready , and when the install takes place you ask for the ONT installed near one end of the cable ( close to where the cable from outside would enter the house ) you then have your router at the other end of the Ethernet cable you fitted yourself inside your house .

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 19:29:24 GMT

ok got it

i was clutching at straws.

googled again about splicing the fiber cable to my existing appears not a field engineer possibility

floor boards or stick with Virgin

I'll google to see if any ISP can use my existing copper coax

thank you for patience with this All best

Re: Cab BT connect to existing open reach fibre cable ?

pippincp — Fri, 30 Jan 2026 19:58:32 GMT

Only VM can use your existing coax cable.

Re: Cab BT connect to existing open reach fibre cable ?

licquorice — Fri, 30 Jan 2026 20:23:13 GMT

Nobody else uses co-ax.

Just use your fibre as a draw rope, it's very simple.

Re: Cab BT connect to existing open reach fibre cable ?

Akimbo — Fri, 30 Jan 2026 23:18:29 GMT

It wont pull I tried . I cant lift those floor boards again.

TBA am of advancing years: back then nobody heard of wifi You had to try and guess future Pulled cables all over houses we moved to for cat something ethernet if it came : It did. so laid this fibre cable for future proof .Engineer who gave it to me assured me it was doddle to connect it some years back

Remember when it came over the telephone wires Had to go out and pee on the earth wire to improve reception in summer.!

You guys have been very helpful If only open reach were in anyway accessible to the consumer Might have known the score sooner

Adios ( thats french by the way )

Dumb Terminal