Conservatory electrics

[GBW]

I am contemplating building a conservatory which is attached to one wall of the house. The contstruction will be dwarf cavity walls with bare brick over a concrete slab. I have been thinking about the power supply and have a couple of questions:

On the inside of the "common" wall is a double socket on the house ringmain (dining room, not kitchen). If I extend this circuit am I exempt from Part P on the basis of "extending existing circuits" or is the conservatory viewed as "outside"? Follr area would be less than 100 sqm and I am looking to adding two doubles. Lighting not an issue.
How do I make cable runs when the walls are bare brick? The only thought I have had so far is to tube in the concrete slab and run up to the underside of surface-mounted sockets. I don't really like trhe idea of running cables around on the underside of the cills in mini-trunking and then running down to sockets in mini-trunking. Would look a bit unsightly. However, if I need Part P this would be someone else's problem...

 

[securespark]

PP needed. Consevertoires are special locs.

 

[crystal ball]

PP needed. Consevertoires are special locs.

Is this a recent development, I thought specials were, Kitchen, bathroom, outside and freestanding outbuildings

 

[Spark123]

The gumph from the SI:
"kitchen" means a room or part of a room which contains a sink and food preparation facilities;
"special installation" means an electric floor or ceiling heating system, an outdoor lighting or electric power installation, an electricity generator, or an extra-low voltage lighting system which is not a pre-assembled lighting set bearing the CE marking referred to in regulation 9 of the Electrical Equipment (Safety) Regulations 1994[14]; and
"special location" means a location within the limits of the relevant zones specified for a bath, a shower, a swimming or paddling pool or a hot air sauna in the Wiring Regulations, sixteenth edition, published by the Institution of Electrical Engineers and the British Standards Institution as BS 7671: 2001 and incorporating amendments 1 and 2."

 

[GBW]

- so why is a conservatory a special location? The only thought I have is that I think building regs regard a conservatory as "external" to the house - does this make it a special location although it is not "freestanding".

Referring back to the other part of my question, waht is the best way of running cables where the walls are brick-finished?

 

[comms]

take a look at page 8 additional note E.
Conservatories are not classed as a special location you do not need to notify any electrical work so long as it's not a new circuit or your not extending a circuit from a special location (kitchen).

http://www.odpm.gov.uk/pub/323/ApprovedDocumentPElectricalsafetydwellings2006edition_id1164323.pdf

 

[Pensdown]

- so why is a conservatory a special location? The only thought I have is that I think building regs regard a conservatory as "external" to the house - does this make it a special location although it is not "freestanding".

Referring back to the other part of my question, waht is the best way of running cables where the walls are brick-finished?

I'll let the others argue the toss about PP.

One diy option is to run the cables in PVC conduit built into the back of the brickwork during construction. As long as the conduit runs within the permitted zones (look in the reference section for details) it should be fine

 

[GBW]

I have done some further checking. I still don't think that a conservatory is a "special location" and i think you can carry out certain modifications such as extending existing circuits by adding sockets.
However on the Residential Landlords Association website under reference to Part P I found this note:

New installation must be certified / notified although modifications in the following areas are exempt:
Bedrooms
conservatories
dining rooms
halls
integral garages
landings
lounge
stairways
studies
tv rooms.

Presumably a new conservatory is by definition a new installation. If the RLA is correct then it is quite clear. I cannot find any reference to such a clear-cut note as this in the actual Part P regs however. It is clear that I can't add a new circuit, but can extend an existing circuit. Does that circuit have to exist in the conservatory (or lounge, bedroom etc) or can it exist external to that room and be extended into it? The regs refer to "new circuits" but seem to apply the definition that a new circuit is one which extends back to the consumer unit.

 

[GBW]

Thanks Comms
That reference makes it quite clear that a conservatory is not a "special location". It also seems to define as "new circuit" as one which runs back to the consumer unit. Is that how you (anyone else?) sees it? So, in a nutshell and keeping it simple:

The conservatory is new, but if I extend from the dining room ring main into the conservatory, is that "extending an existing circuit"? Or creating a new circuit as there is not one there already?

 

[Pensdown]

The conservatory is new, but if I extend from the dining room ring main into the conservatory, is that "extending an existing circuit"? Or creating a new circuit as there is not one there already?

Extension....

 

[ebee]

Anyone come to the conclusion that Part P can be a minefield full of anomolies?

Did I mention phones & alarm cables in bathrooms?

 

[dingbat]

Anyone come to the conclusion that Part P can be a minefield full of anomolies?

Not really. It's all pretty straightforward.

Did I mention phones & alarm cables in bathrooms?

Where's the problem?

 

[RF Lighting]

Did I mention phones & alarm cables in bathrooms?

Where's the problem?

According to Part P, in the list of non-notifiable works it lists "Work not in a special location on: Telephone or extra-low voltage wiring and equipment for the purposes of communications, information technology, signalling, control and similar purposes". It does not however seem to clarify wether carrying out works of the above nature in a special location is notifiable. I think this is where the problem is.

Rob

<edit> quote added

 

[offroader]

Anyone come to the conclusion that Part P can be a minefield full of anomolies?

Did I mention phones & alarm cables in bathrooms?

Who'd want a telephone in the bathroom, unless you often get your toe stuck in tap, and need assistance.

Very rare to even consider sticking a PIR in a bathroom, although I have come accross a few.

 

[ebee]

No.
Telephone cable run thru bathroom.
Might have a window contact or shock sensor in bathroom.
Its notifiable
(Is alarm wiring SELV ? - telephone isn`t)