domestic dwelling advice please

[josh1e]

Hi

(edit. i have read up part p several times now, along with various other info's, i get the impression anything low voltage / video is not covered in anyway & i am freely able to run whatever in terms of data, comms & video, although as soon as i touch mains in anyway i must be able to self certificate? or have someone who is do it? is that right? can someone please confirm it? also there is nothing on running extension leads to different rooms, or the number of plugs which can run from one UPS if the total load doesnt exceed the total capacity of the unit) also there is nothing i have found on any restrictions on how these cables can be run.

I would like to ask someone certified / qualified (which i am not..yet) several questions below, these are common installations i perform & make up "smart home" type installations.

do the following need to be done by an electrician or someone certified or be certified upon there completion? am i doing anything wrong by doing them? or can they be done by anyone? if they need to be done by a sparky / self certified person, can anyone do them & then ask a sparky to certify the installation?

these are all from a central point, for example loft or upstairs boiler cupboard. The boiler manufacturer has stated the boiler runs cool & is externally flued, with over 1ft of space between them they have stated there is no concern to the boiler. Also it does not block access to the boiler for maintenance.

a standard install would include

cctv cabling (12vdc power, 24vac power & video (shotgun cable) & 12v control cable for ptz if required)
telephone master socket relocation, telephone extension point installation, satellite cabling from dish to wall points via distribution amp, (existing dish)
TV ariel distribution systems with 12v sky passthrough
cat5 data network cabling providing wall mounted network points usually in plasterboard pattresses
installation of a knee high metal rack mount cabinet to house equipment
installation of the following items - adsl modem, network hub, patch panel, battery backup UPS, cctv recorder, ariel amplifier, desktop pc.
installation of wall mounted multi function faceplates in bedrooms, lounge, kitchen / diner (cables run inside partition wall) for tv, satellite, phone, network etc.

as a seperate question as i feel this may have seperate answers

installation of loft lighting, taken from existing upstairs lighting circuit
installation of this equipment in a boiler cupboard - any regs against?
installation of a spur in the boiler cupboard, can it be taken from the heating circuit if the heating circuit has its own trip? can i take it from another room? can an extension lead be run through the attic into the boiler cupboard if it is not hard wired & still plugs in?

there are usually some 10+ mains plugs, although these run from a UPS, so only 1 UPS plugged into the spur / extension lead (depending on install)

do the video / low voltage cabling runs have to be run in trunking / be clipped to a joist or follow a specific path through the house / loft space to meet any regs?

Thanks in advance,
josh1e

 

[ban-all-sheds]

do the following need to be done by an electrician or someone certified or be certified upon there completion? am i doing anything wrong by doing them? or can they be done by anyone? if they need to be done by a sparky / self certified person, can anyone do them & then ask a sparky to certify the installation?

All the work you describe comes within the scope of the Building Regulations, as Part P applies to all work on fixed electrical cables or fixed electrical equipment located on the consumer’s side of the electricity supply meter that are intended to operate at low or extra-low voltage and are:
(a) in or attached to a dwelling;
(b) in the common parts of a building serving one or more dwellings, but excluding power supplies to lifts;
(c) in a building that receives its electricity from a source located within or shared with a dwelling; or
(d) in a garden or in or on land associated with a building where the electricity is from a source located within or shared with a dwelling.

Since "extra-low voltage" means AC below 50V and DC below 120V, (Low-voltage means 50 - 1000V AC or 120 - 1500V DC) this encompasses all of the 12V and 24V power cables, all of the aerial cables, all the cat5 and phone cables etc etc.

Some of the work may be notifiable - you really need to carefully read Schedule 2B here.

You'll also find more general information here: //www.diynot.com/wiki/electrics:part-p

A key point to note is that even if the work isn't notifiable, it still has to comply with the Building Regulations, and in any event that's not just Part P, so if you're cutting into the building there are implications for structure, fire transmission, sound resistance, damp penetration etc. If you're doing this as part of a new build then there are disabled access considerations too.

a standard install would include

cctv cabling (12vdc power, 24vac power & video (shotgun cable) & 12v control cable for ptz if required)
telephone master socket relocation, telephone extension point installation, satellite cabling from dish to wall points via distribution amp, (existing dish)
TV ariel distribution systems with 12v sky passthrough
cat5 data network cabling providing wall mounted network points usually in plasterboard pattresses
installation of a knee high metal rack mount cabinet to house equipment
installation of the following items - adsl modem, network hub, patch panel, battery backup UPS, cctv recorder, ariel amplifier, desktop pc.
installation of wall mounted multi function faceplates in bedrooms, lounge, kitchen / diner (cables run inside partition wall) for tv, satellite, phone, network etc.

All involve work on work on fixed electrical cables or fixed electrical equipment which operate at LV or ELV.

Does "knee high" comply with Part M, if that applies?

Do you know the BS 7671 rules for concealed cables?

Do you know what the effect of any thermal insulation will be on the current-carrying capacity of your 12/24V power cables?

installation of loft lighting, taken from existing upstairs lighting circuit

Should comply with BS7671.

installation of this equipment in a boiler cupboard - any regs against?

None "against", but there are some with which it should comply.

installation of a spur in the boiler cupboard, can it be taken from the heating circuit if the heating circuit has its own trip?

If competently done, and in compliance, yes. Obviously you would need to consider what would happen if the whole circuit was isolated to allow the boiler to be worked on.

can i take it from another room?

If competently done, and in compliance, yes.

can an extension lead be run through the attic into the boiler cupboard if it is not hard wired & still plugs in?

Plugging things in doesn't necessarily mean they are not fixed, and therefore that they do not fall within the scope of the Building Regulations. From a best-practices POV such an extension lead would be a bit tacky and unprofessional (IMO), and of course lofts have thermal insulation issues to factor in.

do the video / low voltage cabling runs have to be run in trunking / be clipped to a joist or follow a specific path through the house / loft space to meet any regs?

The Building Regulations (mandatory) have structural, fire, sound, heat loss and condensation requirements of which you need to be aware if you're drilling joists or passing cables through walls or ceilings.

The Wiring Regulations (not mandatory, but a BGI) have requirements for protection of concealed cables and for the proximity of cables such as network, TV, phone, ELV power etc to those running at low voltage.

 

[josh1e]

hi ban-all-sheds

thanks for the very comphrenesive reply.

I have spent time on the part b you mentioned, i am still looking for the official BS7671 document. I wasnt aware of it.

I am happy that where i have had to perforate the exterior walls, i have used fire resistant materials to fill the void around my cables, then a waterproof membrane where possible or the re-fitting of any external cladding over the hole. Where perforations have been made between floors, the part you would be able to see is covered with trunking, above in the cieling is re-covered with unsulation material. (where it is within the floor / cieling void, i havent previously used anything to block any gap left, but this is true also of heating / plumbing installers, there pipework usually has 1/2" holes through cieliengs etc. is this sufficient or should i change it?

as for cabling, the wiki on this forum states it is good practise to follow BS7671 although not compulsory in a domestic dwelling, is this still accurate?

i understand part p in relation to elv / lv. i didnt realise 240v mains wiring was classed as lv ....oooOOooo /shock !! learn something new everyday !!

in dwellings these are not ever new builds, although i do alot of cctv / network installs within company premises, usually for an employer, not under my own company name, so learning these regs & working within them is something i am learning now (a bit late)..

none of the structure has been drilled into / affected. i am careful to leave joists / beams etc alone, except for mounting sockets onto. the easiest path in dwellings are usually cracks / holes which naturally appear under soffits etc. an ip rated box with the hole on the underside & some silicon on the outside, fire resistant expanding foam on the inside usually works nicely.

restrictions within part m relating to access (ie knee high) i couldnt find. in general terms the room is only 1.5ft x 1.5ft, so you cannot "enter" it anyway. a metal box on the floor with cables under trunking down the side of the wall & up through the floor into the box makes no difference to this?

I must admit i am still a little unclear / confused as i am struggling with terminology over notifiable, part p & bs7671 lol... i will spend some time reading tonight & try to clear things up. flow charts in one document state is person qualified, if no go "here" --- "here" states if its adding a socket or light fitting, or elv cables / data / telecomms then its fine. if its a new circuit then its not fine. so that implies there is provision for a normal joe to do this work legally (under part p, bs7671, etc combined)?

thermal insulation i know reduces the carrying capacity of the cable, "usually" 2.5mm is good enough for most ring mains. the elv cables are only carrying around 500ma per cable & are specifically designed for the prupose they have been used. the runs are well within the max length designed for the use also. The cables themselves are low smoke low fume.

could you please explain

Quote:
installation of this equipment in a boiler cupboard - any regs against?

None "against", but there are some with which it should comply.

i dont know where to look to ensure i have complied - thanks.

if the boiler was turned off, my equipment is all connected to a UPS, so there would be no issue. it was a consideration. When u say competently done, can i confirm u mean by a person with a certificate of competence or by a normal joe working competently? (sorry just being certain of your meaning)

I did not realise that i could install a spur / extra socket, so now i know this i will use that method rather than the messy trailing of extension leads. i too feel these are very unprofessional, although had little other choice. the lead was put in trunking where visible & clipped through the loft for safety, so wasnt as bad as it seems.

on mains cables are run next to elv / video / data etc. through the loft space these are clipped loosely using cable ties to "hang" them in a neat path along beams, (a bit like using a wiring tray commercially). as they emerge through into the room, they are concealed in proper trunking, with mains in its own conduit.

thanks for your help,
josh1e

 

[davelx]

i dont know where to look to ensure i have complied - thanks.

http://www.amazon.co.uk/IEE-Wiring-...=sr_1_2?ie=UTF8&s=books&qid=1229084814&sr=8-2

http://www.amazon.co.uk/Electrician...r_1_15?ie=UTF8&s=books&qid=1229084814&sr=8-15

http://www.amazon.co.uk/IEE-site-Gu...=sr_1_1?ie=UTF8&s=books&qid=1229084949&sr=1-1