Power shower

[Gasman1015]

Customer currently has 7kw electric shower, wants 9.5kw but does'nt want mess of having cable upgraded to 10mm.
Consumer unit has rcd and shower on 32 amp mcb.

Have suggested Mira Event XS power shower instead.

Is it acceptable to downgrade mcb to 6 amp and change isolation switch to
3 amp Fcu and 1mm t & e to shower unit, bonding already in place.

Isolation switch currently above zone 2.

Shower unit pump draws 150 watts.

 

[pdcelec]

Customer currently has 7kw electric shower, wants 9.5kw but does'nt want mess of having cable upgraded to 10mm.
Consumer unit has rcd and shower on 32 amp mcb.

Have suggested Mira Event XS power shower instead.

Is it acceptable to downgrade mcb to 6 amp and change isolation switch to
3 amp Fcu and 1mm t & e to shower unit, bonding already in place.

Isolation switch currently above zone 2.

Shower unit pump draws 150 watts.

See the bold bits and tell me that there is a difference?

 

[Gasman1015]

9.5 kw = 9500 / 230 = 41.3 amps

150 watts = 150 / 230 = 0.65 amps

So whats your point.

 

[Adam_151]

What you propose sounds good to me, there is no reason to change the breaker as long as you are taking the 6mm²/10mm² directly into the FCU, oh and by above zone 2, do you mean in zone 3?

 

[Gasman1015]

Thanks , yes it's zone 3, over 2.25 m high.

 

[ban-all-sheds]

Are you a registered domstic installer, or are you planning to notify LABC about this?

 

[Gasman1015]

Not registered yet, will be notifying to LABC, using building notice.

Still planning my options on which one to join, Corgi is out of the equation.

Damn does this mean I won't get your usual bumph BAS.

 

[ban-all-sheds]

DIY Electrical work and the law

On January 1st 2005 legislation came into effect which brought electrical work in dwellings under the Building Regulations, and made it a controlled service. This amendment to the Building Regulations, known as "Part P", imposes safety requirements, and also classifies electrical installation work into two basic categories, notifiable and non-notifiable.

Essentially the distinction is between major work, or work in what are deemed high-risk areas such as kitchens, bathrooms and gardens, and minor work such as replacing switches or adding sockets to existing circuits. (NB to those with a knowledge of the IEE Wiring Regulations, the term "minor work" is used here in its generic sense rather than the meaning defined in the Wiring Regs.)

A very important and fundamental point to note is that DIY electrical work has not been outlawed. It has been brought within the remit of the Building Regulations and cannot be carried out as freely as it was before, and in many cases cannot be carried out without involving your local council, but you may still DIY.

Major work is classed as notifiable, i.e. it must be notified to your Local Authority's Building Control department (LABC). How this happens depends on who does it.

If the work is carried out by an electrician who is registered with one of the organisations who administer self-certification schemes, (sometimes referred to as "Competent Person" schemes) they carry out the work and report the details to their scheme organiser, who then notify the appropriate LABC that the work has taken place, and that it has been certified by the person who carried it out as being in compliance with the Building Regulations. You may be familiar with this method of operation if you have ever had windows replaced by a FENSA member.

If the work is carried out by someone who is not registered with one of the schemes, be they an electrician or another type of tradesman (e.g. kitchen fitter) who has chosen not to register, or a DIYer, then it must be notified to LABC in advance in the same way that any building work which requires their involvement is notified in advance. And just like when you are building an extension, or converting a loft, etc, there is a fee payable to LABC to cover their activities related to checking compliance with the Building Regulations. (But see "LABC Issues" below regarding this).

Another important point to note is that apart from a Building Inspector, nobody can certify someone else's work as being compliant with the Building Regulations. Unless arranged by or in cooperation with LABC, a 3rd party electrical inspection is of no value in terms of complying with the law.

The full text of the legislation can be found here: http://www.opsi.gov.uk/si/si2004/20043210.htm and it is worth making the effort to read it, and understand it, because there is a lot of misinformation on the Internet, some of it put out by organisations with a vested interest in pretending that DIY work is illegal, some of it by LABCs who have either misunderstood the legislation, or who are also attempting to mislead the public in order to reduce the amount of work notified to them by non-self-certifying people, some of it, surprisingly, by the ODPM themselves (The Office of the Deputy Prime Minister were responsible for the legislation), and much of it on electrical advice and discussion fora like this one.

At the time of writing (September 2005), the following work was classed as not needing notification to LABC:

1. Work consisting of -

(a) replacing any socket-outlet, control switch or ceiling
rose;

(b) replacing a damaged cable for a single circuit only;

(c) re-fixing or replacing enclosures of existing
installation components, where the circuit
protective measures are unaffected;

(d) providing mechanical protection to an existing
fixed installation, where the circuit protective
measures and current carrying capacity of
conductors are unaffected by the increased thermal
insulation.


2. Work which -

(a) is not in a kitchen, or a special location,

(b) does not involve work on a special installation, and

(c) consists of -


(i) adding light fittings and switches to an
existing circuit;

(ii) adding socket outlets and fused spurs to an
existing ring or radial circuit; or

(iii) installing or upgrading main or supplementary
equipotential bonding.


3. Work on -

(a) telephone wiring or extra-low voltage wiring for the
purposes of communications, information technology,
signalling, control and similar purposes, where the
wiring is not in a special location;

(b) equipment associated with the wiring referred to in
sub-paragraph (a).

The terms "kitchen", "special installation" and "special location" are defined in the legislation.

Like any law, things can change, and you are urged to ensure that you make yourself familiar with the law as it stands now, not necessarily as it was when this document was written.

The starting point on the ODPM website for information related to Building Regulations is http://www.odpm.gov.uk/stellent/gro...ments/sectionhomepage/odpm_buildreg_page.hcsp and a list of the relevant legislation can be found at http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/page/odpm_breg_600270.hcsp .

It is in the nature of the Internet for sites to change, and it may well be that today, when you are reading this, the links above no longer work, and you will have to search for the pages you want.


Useful Information

On the ODPM website there are a number of "Approved Documents"
( http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/divisionhomepage/br0041.hcsp ). These are not definitions of the law, nor do they tell you what you must, or must not, do. Instead they give guidance on ways in which the law can be satisfied. They do point out that you are not obliged to adopt any solution contained in them if you prefer to meet the requirements in another way, but that said they are useful as they contain common sense advice and often there is no good reason not to adopt the solutions they contain.

Approved Document P can be found here: http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/page/odpm_breg_br1007.pdf .


Technical Requirements

The technical requirements laid down by Part P are remarkably simple. They are:

P1 Reasonable provision shall be made in the design, installation, inspection and testing of electrical installations in order to protect persons from fire or injury.
P2Sufficient information shall be provided so that persons wishing to operate, maintain or alter an electrical installation can do so with reasonable safety.

It is worth noting however that they apply to all work, not just notifiable work, no matter who does it. So a DIYer adding a socket or a fused spur to a ring final circuit must work to the same technical standards as a registered electrician doing a complete rewire.

The biggest practical issue that arises is testing. To carry out testing of electrical circuits requires expertise and equipment, neither of which are likely to possessed by the average DIYer. So although Part P allows a DIYer to replace an entire circuit cable if it is damaged, without notification, it is arguable that he could not be sure that he had done it properly unless he carried out a series of tests on it, something he would probably be unable to do.


The IEE Wiring Regulations, aka BS 7671

Surprisingly, perhaps, Part P does not alter the status of the Wiring Regulations. They are still non-statutory, and there is still no legal requirement to adhere to them in domestic installations. This is a source of great discomfort to many electricians, and some of them will jump through hoops to try and prove that they are mandatory, but the fact remains that they are not.

HOWEVER, adherence to them is a very good way of ensuring that you meet the technical requirements of Part P, and you would need a very good reason, and a very good understanding of what you were doing, to decide to not adhere to them.


LABC Issues

As mentioned above, some LABCs are spreading misinformation, either by accident or design, about the status and acceptability of electrical work done by DIYers or other non-registered people.

These include:

1) Stating that such persons simply cannot carry out notifiable work, and that it must be done by registered electricians. The legislation referenced above, Statutory Instrument 2004 No. 3210 The Building (Amendment) (No.3) Regulations 2004 makes it quite clear that this is not the case. LABCs are not allowed to refuse to process Building Notices submitted by non-registered people.

2) Stating that work carried out by a non-registered person must be inspected and tested by someone who is registered. Again, there is no mention of this requirement in the statutory instrument.

Recently the ODPM issued a circular to local authorities making it absolutely clear that they are not allowed to do this:

http://www.odpm.gov.uk/stellent/groups/odpm_buildreg/documents/page/odpm_breg_037024.hcsp

3) Attempting to impose extra charges to cover the inspection and testing of work done by a non-registered person. An LABC may well elect to subcontract inspection and testing if they do not have the capacity to do it themselves, but they are not allowed to charge extra because of this – the cost to them of subcontracting must be borne by them

Individual local authorities co-ordinate their services regionally and nationally (and provide a range of national approval schemes) via LABC Services. (http://www.labc-services.co.uk).

I recently posed LABC services the following question:

"My local Building Control dept has told me that because of staffing problems they are unable to inspect some building work, and will have to sub-contract it, and that I will therefore have to pay this cost on top of their fees.

Are they allowed to do this?"

Their reply was:

"Building Regulation fees are set to a scale that embraces the whole scope of what may be necessary in respect of checking and approving the plans and inspecting the work. The input necessary can vary according to the circumstances of a specific scheme, but the fees are not variable due to this feature.

The local authority has a legal duty to carry out the Building Regulation function to a proper degree. This can also vary in extent according to the demands of any scheme and considerable discretion rests with the authority. However they are responsible to give a proper service within the fee and cannot charge extra for the reason you mention. Indeed if they failed to inspect yet still charged you might have a case for a refund."

 

[Gasman1015]