Started the wiring on my first new build.

[Norv]

Customer is using dot & dab for the plasterboard. Shall I leave the wiring on the face of the internal blockwork & use capping & chase the back boxes in ? Or use dry lining backboxes like I have seen in the past ?

Do I chase the back box in so the front of it is flush or leave it sticking out a bit ?

If I chase the backbox in & dont chase the wiring in how can I get it through the grommet in the backbox ? Do I chase a little bit out for the wiring next to the backbox ?

Thanks

 

[Lectrician]

Simple stuff really


It depends on the dot and dabber, but generally, you sink the back box in by 1/3 - The dabs and board make up the other 2/3. Some dabbers are happy with the box being stuck straight onto the wall, as they use larger than usual dabs.

DONT use dry liners.

You can clip the cables tight to the wall if you wish, or put some capping over the top. You may have to chomp some block out to allow the cable to smoothly enter your grommeted hole.

 

[Norv]

Thanks Lectrician. Simple stuff I know, just wanted to know the technique

 

[Norv]

Oh yeah, got to put the BT sockets in aswell, one master & all the rest extensions I suppose. Is there a special little way of doing it or just a case of running the wire in ?

 

[electronicsuk]

Oh yeah, got to put the BT sockets in aswell, one master & all the rest extensions I suppose. Is there a special little way of doing it or just a case of running the wire in ?

If there aren't too many extensions then just run each one back to the master with 2/3 core twisted pair cable, if you're really smart then you could use cat 5 to allow the customer to easily upgrade when IP phones become more mainstream.

You could go from the master and then daisy chain the secondary outlets as if it were a radial circuit, but this is less flexible and doesn't give a lot of scope for future upgrades. If you go this method then don't bother using cat 5, as it must be wired point to multipoint.

 

[Norv]

Thanks electronicsuk. Whats the benefit from putting BT sockets in. Our phones in my house just plug into the 230V (1 plugged into the BT master socket) & there is 4 around the house all linked together.

 

[Lectrician]

For a bog standard house, just daisy chain the sockets from where BT will fit THEIR master (sink a 25mm box in at this location, either with a hole directly out the back through the outside wall, or some 20mm poly duct to outside). BT will wire from the network to this master point.

Use 3 pair CW1308 cable, 4 pair if your budget allows. Scope for extra lines then. Pointless daisy chaining Cat5e, and pointless star wiring cat5e if you do not flood wire the place.

Dont forget to suggest a telephone point behind TV locations - remember that sky boxes need a phone line for interactive use and for multiroom etc.

Are you installing TV points aswell?

 

[Norv]

I am installing TV points aswell. It says TV/FM on the drg

 

[Taylortwocities]

Per the above, you'll need hardwired Tel points at places where ADSL (braodband) devices are connected also near the SKY box

Do not run you tel cables near mains cables or you'll get a nice 50HZ hum on your telephone.

Chack whats needed for the tv. you may need a downlead from terrestrial then maybe an uplead if the SAT box is feeding other TVs. Depends on what the custoemr wants.

 

[Lectrician]

Generally 3 coax from loft to main TV location. These go into a double back box, along with the phone cable, 35mm deep.

One coax to all other locations, unless they want to use digiboxes at other locations too.

FM and UHF are diplexed into the one coax for the secondary locations, and FM, UHF and SAT are triplexed onto one coax for the main location. The other two coaxes to the main location are for a second sat for sky plus, and an uplink for the secondary locations.

Dont forget a socket in the loft where the booster is to go.

It is typical to leave the coax's in the loft for an erial guy to terminate. He will fit the aerial as appropriate, and the minidish for the sky.

 

[Taylortwocities]

And use good qual satellite coax everywhere, not cheapo coax
.

 

[Lectrician]

CT100, PH100 etc

 

[Sureitsoff?]

Generally 3 coax from loft to main TV location. These go into a double back box, along with the phone cable, 35mm deep.

dont forget that sky+ needs two cables from the dish to the sky box

 

[Lectrician]

YES, I have taken that into account above.

Generally on new builds you do not run cabls to the dish location, just to the loft.

3 coax to the main viewing location is all that is required for sky and sky+ though.

I have a loft box which has 4 LNB inputs. 2 for the main location, and the other two are diplexed onto two of the room outlets to allow a digibox to be plugged in in these rooms. A triplexor outlet is used with UHF, FM and SAT.

 

[electronicsuk]

Thanks electronicsuk. Whats the benefit from putting BT sockets in. Our phones in my house just plug into the 230V (1 plugged into the BT master socket) & there is 4 around the house all linked together.

That's probably because you're using cordless phones, but any wired telecoms devices will need to be plugged directly into a telephone socket.

I still stand by my comments regarding star wiring and cat 5 for telecoms - IP phones are going to become mainstream devices over time, and given how cheap cat5 is these days you can't really go wrong.