DIY home automation, notification, Part P?

[a546345]

I thought I'd go for a benign, non controversial thread title!

If I, as a DIYer, approached you, as an electrician, asking how we could work together to legally interface a home automation system with various existing lights and appliances, what would be your concerns and discussion points? The objective being for the installation to be legal and safe.

The home automation system may provide 12V or 5V outputs suitable for driving relays, and typical interfaces might be relays, solid state relays, and contactors all with screw terminals.

Let's initially consider 3 scenarios.

1. Modify the cabling to an existing light fitting in a non notifiable place (eg. bedroom) to provide control via automation while retaining local control via the wall switch. Possible Approach :- intercept and break out the cable to the light switch in either a JB or a plastic enclosure in an accessible place. Relay installed in the enclosure with the contacts duplicating the action of the wall switch. CAT5 or alarm cable used for the control signal to the relay. Contacts on relay sized appropriately for relevant MCB/RCBO. I am aware that the automation would switch the light on with no way of switching it off again from the local wall switch.

2. Same as 1, however the light fitting (but not the wiring intercept point) is in a kitchen or bathroom.

3. Modification of the 240V cabling from the boiler to the room thermostat to allow control via automation. Possible approach same as 1. ie, relay in a box.

1st question. Would a relay be classed as a switch in 2.c.i of Schedule 4? I used this link. http://www.legislation.gov.uk/uksi/2010/2214/schedule/4/made . Would any of these scenarios be non notifiable?

2nd question, Would you be happy with the approach above or would you suggest a different solution? Assume a retrofit, so not practical (unfortunately) to route all supply and switch cabling to a central point and have a bank of DIN mounted relays.

Other questions probably to follow...

 

[EFLImpudence]

Descriptions of Work where no Building Notice or Deposit of Full Plans Required
1. Work consisting of—
(a)replacing any fixed electrical equipment which does not include the provision of—
(i)any new fixed cabling, or...

Does that not cover all your proposed work?

Yes, a relay is a switch.

 

[a546345]

EFLI, I'm working through the multiple negatives - are you saying that all my proposed work is notifiable, or that none of it is notifiable?

 

[EFLImpudence]

New fixed cabling in any room is notifiable.
(It is not necessary to notify work which consists of replacing electrical equipment which does not include the provision of new fixed cabling)

However, if you were expecting to have to notify some of the work then notifying all of it will make no difference.

 

[a546345]

I was expecting 3 to be notifiable (as heating controls), and 2 to be a grey area.

However, on scenario 1,

1. I'm just cutting an existing cable and joining it back up again in a box, Is this really "adding new fixed cabling"?

2. Regardless of the fixed cabling question, 2.c.i says that adding switches to an existing circuit is not notifiable, so therefore I could add my relay "switch" under this clause? If any additional fixed cabling was actually required, then this is also non notifiable under this clause?

 

[RF Lighting]

New fixed cabling in any room is notifiable.
(It is not necessary to notify work which consists of replacing electrical equipment which does not include the provision of new fixed cabling)

However, if you were expecting to have to notify some of the work then notifying all of it will make no difference.

Are you sure about that?

I thought the installation of new cabling and accesories is ok, as long as it's not a new circuit, and it's not in a special location.

 

[EFLImpudence]

1. No that isn't notifiable in itself.
Are you saying there will, in fact, be NO new fixed cabling anywhere?

2. No. 2.c.i doesn't exempt you from 1.a.i

As I said, though, one notification could be made for everything - same single fee - makes no difference.

 

[PrenticeBoyofDerry]

Scenario 2 as it is a special location/kitchen/bathroom.
If you were to alter/add to the circuits cabling, it would be notifiable.
Also you would need to add RCD protection, if not already present.

 

[EFLImpudence]

New fixed cabling in any room is notifiable.
(It is not necessary to notify work which consists of replacing electrical equipment which does not include the provision of new fixed cabling)

Are you sure about that?

Isn't that what it says.
I think I have paraphrased it correctly but, if not -

Descriptions of Work where no Building Notice or Deposit of Full Plans Required
1. Work consisting of—
(a)replacing any fixed electrical equipment which does not include the provision of—
(i)any new fixed cabling,...

I thought the installation of new cabling and accesories is ok, as long as it's not a new circuit, and it's not in a special location.

 

[a546345]

Appreciate the responses - thanks guys. Can I pick this apart slightly please?

2. No. 2.c.i doesn't exempt you from 1.a.i

How would I add a new light or switch to a normal existing circuit (forget the automation for a minute) without adding new fixed cabling?

Scenario 2 as it is a special location/kitchen/bathroom.
If you were to alter/add to the circuits cabling, it would be notifiable.
Also you would need to add RCD protection, if not already present.

If the wiring to the kitchen light is, for example, in the loft and alterations can be carried out without going anywhere near the kitchen, why would this be notifiable?

Similar discussion as adding an in-line fan to a bathroom where all the electrical work is in the loft.

I'm genuinely trying to understand the boundaries here - apologies if it comes across as nitpicking.

 

[PrenticeBoyofDerry]

I would say if the termination was made within the special location, kitchen, bathroom regardless of the route it took to get there, it would be deemed notifiable.

 

[EFLImpudence]

Appreciate the responses - thanks guys. Can I pick this apart slightly please?

Yes.

2. No. 2.c.i doesn't exempt you from 1.a.i
How would I add a new light or switch to a normal existing circuit (forget the automation for a minute) without adding new fixed cabling?

1.a.i states replacing - adding which would involve new fixed cabling is notifiable.

Scenario 2 as it is a special location/kitchen/bathroom.
If you were to alter/add to the circuits cabling, it would be notifiable.
Also you would need to add RCD protection, if not already present.

If the wiring to the kitchen light is, for example, in the loft and alterations can be carried out without going anywhere near the kitchen, why would this be notifiable?

In the loft, alterations would not be notifiable.
New fixed cabling is.
If you think the light in the kitchen is in the loft all well and good.

Similar discussion as adding an in-line fan to a bathroom where all the electrical work is in the loft.

I cannot read into 1.a.i anything which exempts new fixed cabling from notification.

I'm not trying to brow-beat you. If you disagree then do not notify.

I am sure you can read the regulations and interpret them as well as anyone else.
They are not very well written with regard to language or logic.

 

[ban-all-sheds]

No. 2.c.i doesn't exempt you from 1.a.i

That doesn't make any sense.

Schedule 4 is not a list of what is notifiable, from which you may or may not be exempted, it is a list of what is not notifiable.

You start at the top, with the position that the work is notifiable.

You read down the list.

If you find a match with the work, you stop - it is non-notifiable.

If you get to the end without a match the work is notifiable.

Just because the work doesn't match one description that doesn't mean it has to be notifiable - were that to be the case then for work to be non-notifiable it would have to match everything, which would clearly be nonsense.

1.a.i states replacing - adding which would involve new fixed cabling is notifiable.

Not necessarily.

1(a) is the exemption for replacements. If the work is not a replacement then the provision about no new fixed cabling is irrelevant.

Para 2 of Schedule 4 covers additions, and it clearly says that unless the work is in a kitchen or special location, or it involves a special installation, the addition of switches to an existing circuit is non-notifiable. As is adding new lights, sockets & FCUs.

So, unless you want to try and claim that in practice Para 2 exempts nothing because to add switches means adding new fixed cabling....

I am sure you can read the regulations and interpret them as well as anyone else.

I'm not sure everyone can read and interpret them equally well.

They are not very well written with regard to language or logic.

Schedule 4 is pretty clear.

 

[EFLImpudence]

I know we have been through this before but -

1. Work consisting of—
(a)replacing any fixed electrical equipment which does not include the provision of—
(i)any new fixed cabling...

Does that not mean if the work includes new fixed cabling it is notifiable?


If you reply "only as far as replacements are concerned" then...

...is it non-notifiable to add light fittings and switches which do include new fixed cabling?

 

[ban-all-sheds]

I know we have been through this before but -

1. Work consisting of—
(a)replacing any fixed electrical equipment which does not include the provision of—
(i)any new fixed cabling...

Does that not mean if the work includes new fixed cabling it is notifiable?

No.

It means that the work does not become exempt via provision 1 in Schedule 4.

It does not mean that it cannot become exempt via another provision.

If you reply "only as far as replacements are concerned" then...

...is it non-notifiable to add light fittings and switches which do include new fixed cabling?

Subject to 2(a) and 2(b), yes.