IET logo
 
IET
Decrease font size
Increase font size
Topic Title: Metering for Part L
Topic Summary: Where is it requierd
Created On: 05 November 2010 12:48 PM
Status: Post and Reply
Linear : Threading : Single : Branch
Search Topic Search Topic
Topic Tools Topic Tools
View similar topics View similar topics
View topic in raw text format. Print this topic.
 05 November 2010 12:48 PM
User is offline View Users Profile Print this message



burn

Posts: 115
Joined: 06 June 2003

I understood metering was required to split energy used by lighting, small power, heating and ventilation in building where Part L applies and this is any building over 50m2. (with a few exempitions)
Also, automatic data collection is required for floor areas over 1000m2.
However, looking the MEM distribution board webpage on metering sulutions-part L compliance, they say separate metering is required in buildings over 500m2. I cannot find any reference to this figure in part L.
Does anyone know where this figure comes from and am I missing some important document or guidance note.
 05 November 2010 01:27 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

I'm afraid they are just a tad out of date - the 500m2 requirement was in Part L 2002.

It might be useful to have a canter through CIBSE TM 39 2006 and 2010 versions. A browse through CIBSE TM 46 is also useful to determine what benchmark criteria you are trying to achieve

Regards

OMS

-------------------------
Failure is always an option
 20 February 2013 07:10 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

Bump....

I have been at the theatre job today in the company of the electrician who is going to change the home made board which we discussed a while back.

He wants to include metering for lighting and small power into the board, in accordance with part L requirements so I'm looking at part L right now. I'm looking at the section for existing buildings which are not a dwelling.

I cannot find this requirement. Could you please guide me to it?

Edit: This is a DB change and the building is not going through refurbishment.


Zs
 20 February 2013 07:41 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

The requirement is at 4.33 et seq of part L2B -

If you are just swapping out DB's, then you are not providing or modifying a controlled service. Equally as you aren't doing any other work, there is no requirement to consider consequential improvements.

Good practice says you should think about providing metering, but in this case part L doesn't require you to do it.

Assuming this is one of a number of boards, metering a single DB is pointless anyway as the objective is to capture 90% of the primary energy broken down by end use.

If and when you get round to a metering strategy for the site as a whole, it may well be easier to meter at the main switchboard end.

Don't get hung up on seperating lighting from power etc either - a lump load not exceeding 50kW or say 500m2 of floor area would be perfectly aceptable as a solution for Part L compliance (if you wished to provide a single meter for the DB)

regards

OMS

-------------------------
Failure is always an option
 20 February 2013 07:51 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

Mwah.

I had found the controlled bit and had discounted it and spent some time scouring the rest.

Thank you OMS

Zs
 20 February 2013 07:56 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

My pleasure Madam - have a good one

OMS

-------------------------
Failure is always an option
 20 February 2013 09:08 PM
User is offline View Users Profile Print this message


Avatar for Martynduerden.
Martynduerden

Posts: 3211
Joined: 13 July 2008

What is the differences between this thread and This one?

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com
 20 February 2013 09:14 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

New build and existing I suspect Martyn - different requirements

regards

OMS

-------------------------
Failure is always an option
 20 February 2013 09:25 PM
User is offline View Users Profile Print this message


Avatar for Martynduerden.
Martynduerden

Posts: 3211
Joined: 13 July 2008

Originally posted by: OMS

New build and existing I suspect Martyn - different requirements

regards

OMS


Ah l read jobbo's post as existing undergoing significant changes.

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com
 21 February 2013 09:23 AM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

Originally posted by: Martynduerden

Originally posted by: OMS

New build and existing I suspect Martyn - different requirements

regards

OMS


Ah l read jobbo's post as existing undergoing significant changes.


It was the Cat A fit out of the office space (approx 200m2) as I read it Martyn - not really a parallel to Zs's site having a DB swap out.

Would a metering strategy be of value on the job - I would say yes, would adding a few isolated meters to existing DB's without that strategy in place - probably not - is it a Part L requirement - in this case no.

At best, a review of space at the DB incomer might lead the designer to consider a small extension box in preparation for retrofit CT's - alternatively there is usuually enough space in most Type B dist boards to pack in a few split core CT's at a later date without any drama. A voltage reference would be off the avialable spare ways in practice.

Alternatively, it may be easier to retrofit at the source end - I don't know, I haven't seen it.

I read the post as the inclusion of meters is something the installer wanted - Zs appears not to agree and was canvasing a second opinion to that arrived at from a read of Part L2B.

Regards

OMS

-------------------------
Failure is always an option
 21 February 2013 08:09 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

Sort of. The installer said he wanted to put them in and I knew very little about them so I was looking it up to see if it was necessary. In truth, to see if I had missed something in my comments about the original DB change.

My client has already paid for this board to be replaced once. As you know it was with the home made board. It is being changed again at my suggestion/demand for their safety and their insurance. So they are going to be paying for it again and will not be able to pass the cost of it on.

Separte metering may well happen in the future but if it were required I would need to flag it with them and it could be a new expense which could be passed on ( or not) to the theatre.

Just trying to do right by the regs and right by my client, who trusts me to check up on these things. That's the role I play with this client.

I got the commission for the full EICR on the theatre yesterday. Very pleased about that.

Tomorrow I shall screw some sockets to a wall on a building site and bung a bit of 10mm bonding under some floorboards. Life's rich tapestry.

Thank you.

Zs
 21 February 2013 08:20 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

Separte metering may well happen in the future but if it were required I would need to flag it with them and it could be a new expense which could be passed on ( or not) to the theatre.

Just trying to do right by the regs and right by my client, who trusts me to check up on these things. That's the role I play with this client.


OK - perhaps worth suggesting they consider getting a metering strategy drawn up (as in the theatre people) - it would be a modest cost, something you could do for them without too much drama and it would help inform thier future investment direction - ie it might become a house rule that new DB's must have space for CT's for example.

It would be pointless however unless they were broadly willing to act on the eventual meter readings (and that may be influenced by local or remote reading) - and benchmarking might be a bit of an ordeal as well - not much to compare with I suspect.

At the end of the day - Part L is about energy - and it's true that if you can't measure it, you can't manage it

Regards

OMS

-------------------------
Failure is always an option
 21 February 2013 08:29 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

Well, I have a photo on my phone from today's inspection. Not the theatre somewhere else. It is of an electricity bill for the last quarter.

£19,111.81

The previous quarter was £11,671.60

It's a crime don't you think? They are not even in residence for most of the year.

Now these people have metering for the big house with a pool house on one meter, stable block (no horses, just shed things) on another and garage with cottage on the third. 9kW of convector heaters running 24/7 in the shed with no door on it, and so on. They're kindof rich if you get my drift, but only about ten bedrooms in the house.

I suggested they might like to have a look at their consumption and at saving some polar bears. Oh how I wish ground source really worked. They have acres of park with deer running around which would be perfect for a bit of slinky behaviour.

Zs
 21 February 2013 08:37 PM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

Ground source works just fine - I could point you to numerous examples - it just needs to be designed right, installed right, commissioned right and operated right.

That's one hell of a leccy bill though

It's thier money I guess - but thier emissions also influence my planet - so they need to a get a grip on things for sure.

Keep advising on the need for an energy audit (and some sub metering) in the not to distant future - potentially a small saving on that sort of money per annum would make the fee seem inconsequential

Regards

OMS

-------------------------
Failure is always an option
 21 February 2013 08:51 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

This is where part L strikes home, not a DB change in an old building.

The emissions and the effect on the planet are what bother me.

Somewhat off the part L track but on arrival I was proudly shown a video of our heir to the throne visiting the outbuilding I was inspecting. Last summer. It was built especially for the visit 18 months ago and is now showing some problems. It was never certified. But the visit happened. These people paid a fortune for an installation which is truly awful. They put their trust in the installer.

Fortunately, I suppose, the part of the installation which I was inspecting was so critically dangerous that I get to write a report for the estate management company this weekend. I switched it off it was so bad and I do not do that lightly. Because this will be more than a set of forms I get a chance to mention consumption.

Zs
 21 February 2013 09:31 PM
User is offline View Users Profile Print this message


Avatar for Martynduerden.
Martynduerden

Posts: 3211
Joined: 13 July 2008

Originally posted by: Zs

This is where part L strikes home, not a DB change in an old building.


True enough, assuming this is a single DB change I'd be inclined to agree, but and it's a big but, from all the posts about theatre on here, I was under the impression that significant new electrical work had taken place and that trend was to continue to improve the infrastructure?

I assume that they have no energy meters and no metering strategy, I guess it has to start somewhere and whether that is slowly n cheaply in each changed DB or expensively, limited later to metering any sub mains is worth some consideration.

I also noted controlled service it seems that it might be within that definition, part L does have application to existing commercial premises.


The emissions and the effect on the planet are what bother me.
Zs


Quite, I think I would be inclined to fire it back to your client and requesting information (likely non existent) on their energy policy.

If it turns out not to be a requirement, I wonder how long it will be before it is?

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com
 21 February 2013 10:24 PM
User is online View Users Profile Print this message



Zs

Posts: 2634
Joined: 20 July 2006

OK Mart, Controlled services.

You press a light switch and the lights come on. You Press it the other way and the lights go off.

Are you suggesting that this is a controlled service?

I'm not.

This is where you and I differ pal. If I need to find you a clause in a printed book, then I'll look it up for you and spend time copying it out for your files. For a fee if I don't care and not if I do. If I need to find you a way of making your existing installation safe and compliant, then I'll do that for you too.

My client gives me a brief and I make a point of understanding their requirements. Sometimes I have to break bad news. Sometimes good news.

The good news is that this new DB does not require a few hundred pounds' worth of metering equipment.

Maybe, just maybe, I will be commissioned for the re design of the installation some time soon.

But don't beat me up for wanting to do right by my client and the saftey of the public please. I do reality.

Zs

The polar bear issue is a different client so I have missed it off this post.
 21 February 2013 11:11 PM
User is offline View Users Profile Print this message


Avatar for Martynduerden.
Martynduerden

Posts: 3211
Joined: 13 July 2008

Originally posted by: Zs

OK Mart, Controlled services.

You press a light switch and the lights come on. You Press it the other way and the lights go off.

Are you suggesting that this is a controlled service?

I'm not.



Agreed, a light switch is not a controlled service, but I wasn't suggesting it was, I was mearly pointing out that part L applies to energy efficiency in commercial buildings whether them new or existing and therefore electrical infrastructure by definition is a controlled service.


This is where you and I differ pal. If I need to find you a clause in a printed book, then I'll look it up for you and spend time copying it out for your files. For a fee if I don't care and not if I do. If I need to find you a way of making your existing installation safe and compliant, then I'll do that for you too.


Not sure I follow you there, like you, I obviously care about safe and complient, where we differ is I don't see the point in "polishing a turd" to save a few quid.

I couldn't care less about the clients wallet - it's not my problem, if something is crap I will say its crap If it does not meet the regs, likely I will tell them, otherwise why bother?

As you know I do care about the clients wallet when shockingly bad work takes place and they pay for it because its now deemed safe, it make my blood boil.

I'm not talking about pin straight cables - that's my issue, I do what makes me sleep at night as do you, you know your one of the good guys I don't need to blow your trumpet.


My client gives me a brief and I make a point of understanding their requirements. Sometimes I have to break bad news. Sometimes good news.


The requirements of most clients are simply cheap and safe which is a good start, most couldn't care less about the regs. Personally I fail installations that others may pass mainly because its either right or wrong.


The good news is that this new DB does not require a few hundred pounds' worth of metering equipment.


I most likely disagree, purely because part L applies, it's a controlled service, I know not the sq meterage of the building, but I suspect it's over 500, I don't know the extent of the works carried out or the future plans but I suspect it may involve significant work.


Maybe, just maybe, I will be commissioned for the re design of the installation some time soon.


I hope so for you, but I suspect it will be patched up untill it burns down, obviously not your fault, and meters wont stop it,but they might contribute to doing what you wish in the long term, which I suspect is to look after a client and save them funds. I suspect its just typical clients who won't spend or do what is really required.


But don't beat me up for wanting to do right by my client and the saftey of the public please. I do reality.

Zs.


Who's beating you up? just opinions, I believed I've earned the right to express as have you, I'm not suggesting you are not doing right by anyone.

Reality - well it's as real as we choose, I do facts when it comes to clients. I don't particularly care if in my opinion the regs are pointless ones, a nightmare to rectify, or might just upset the applecart.

Generally goes.

"Is it dangerous?" Not immediately
"Does it meet the regs that it should ?" No.
"Should I spend money correcting it?" Yes.
"Will the report be satisfactory if I don't?" No.

The trouble with clients is they are guided by forms such as the EICR which are totally useless, I mean codes 2 & 3 are useless but that's another topic.

-------------------------
Regards

Martyn.

Only a mediocre person is always at their best



www.electrical contractors uk.com

Edited: 22 February 2013 at 12:07 AM by Martynduerden
 22 February 2013 10:14 AM
User is offline View Users Profile Print this message


Avatar for OMS.
OMS

Posts: 18943
Joined: 23 March 2004

I suggest you both go and read the definition of controlled service and controlled fitting - it's a service or fitting in relation to which Part G, Part H, Part J, Part L and Part P of the Building Regulations apply.

Fixed building services are defined as any part of or any controls associated with fixed internal or external lighting but not emergency lighting or specialist process lighting and any fixed system for heating, hot water service, air conditioning or mechanical ventilation.

Zs and Martyn - Lighting is a controlled service - so what switches that light on and off is a controlled service - it's why we have control factors in energy calculations to account for what switches that fitting on and off and also sets limits on the efficacy of that fitting - it's also why we consider it a "end use" and consider sperate metering. Emergency lighting is exempt - it dos not have energy implications for a building so it can be as inefficient as you like - the safety function over rides the energy burden

Martyn, electrical infrastructure is not a controlled service - the requirment is to capture at least 90% of the primary energy consumption broken down into end use. Metering is a requirement of Part L - read Part L2B. Swapping out a DB is not a trigger for implementing metering in an existing building. You are not adding or modifying a controlled service, you have not triggered consequential improvements. You have not added anything that changes the energy status of the building.

The wording is "reasonable provision" ............." energy meters"............. "building services systems provided as part of the works"

You might also want to take a look through the non domestic compliance guide - effectively second tier documentation to Approved Document L to get a feel for what controlled services are all about and why controlled fittings have an impact on the use of fuel and power

As for the clients wallet, you have as much a duty to that as you do to thier technical advice and means of statutory compliance. In everything we do, bar one or two notable exeptions we have the basis of English law - " reasonably practicable" - that by definition requires a balance of the quantum of risk against the time, cost and effort required - the test being the balance must be disproportionate.

"Is it dangerous?" Not immediately
"Does it meet the regs that it should ?" No.
"Should I spend money correcting it?" Yes.
"Will the report be satisfactory if I don't?" No.


I think the key point in all of that, is the consideration that much regulation is not retrospective - the two words missed out are "current" and "obligation" in points 2 and 3 respectively, which changes the outcome of 4 dramatically.

Now play nice

regards

OMS

-------------------------
Failure is always an option
Statistics

See Also:



FuseTalk Standard Edition v3.2 - © 1999-2014 FuseTalk Inc. All rights reserved.