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Topic Title: Part L - Are split metered distribution boards necessary?
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Created On: 14 February 2013 02:15 PM
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 14 February 2013 02:15 PM
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Mattysmith1983

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I'm having many battles with Contractors in regards to the requirements of split metered distribution boards.

Part L itself directs toy to CIBSE guide TM39, but even in here its hard to understand if they are specifically required. It mentions if you can estimate the lighting consumption actually you don't need to meter the lighting.

Does anyone know exactly what are the requirements in regards to split metering of the small power & lighting, and are they the same for refurbishment as new builds.
 14 February 2013 02:26 PM
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OMS

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The Building Regulations Part L2 effectively call for sub-metering at any final distribution board in non-domestic premises with a floor area greater than 500 square meters. Ideally, lighting and small power loads supplied from a common board should be metered separately. The Regulations also require automatic meter reading and data collection in buildings with a total floor area greater than 1,000 square meters.

L2 does allow for consumption to be calculated by other means, for example, by measuring the run hours of equipment that operates at a known load - difficult to do that for lighting though

The Regulations call for separate metering for final distribution boards greater than 50kW, as well as defined loads of lower demand (humidifiers, fans etc)

You won't find a "rule" that says do XYZ. It's up to the designer to specify the requirements to achieve compliance.

If you are having a battle with contrators, what does your spec say - and is what it says robust enough to give you what you want, not what the contractor feels is compliant.

If your spec says comply with BS 7671 and Part L then you probably don't have much of an argument - if you have provided a metering strategy document in accordance with CIBSE TM 39, then you should be getting what you want.

The short answer, is there is no requirement to have split metered DB's - that's only one way of showing compliance.

Regards

OMS

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Failure is always an option
 14 February 2013 02:33 PM
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Mattysmith1983

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Thanks for this OMS - My spec specifically asks for Split metered DB's but as always they think they can do without them and save a penny or too.
 14 February 2013 03:10 PM
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Mattysmith1983

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Another question in TM39 :2009 it highlights on page 9 under the New buildings: Part L Compliance - Metering of lighting for new and existing buildings (to record the lighting energy consumption) should meet the minimum standards in table 49. Does anyone know where this table 49 exists? Is not in the TM or Part L documentation.
 14 February 2013 03:23 PM
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Mattysmith1983

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Sorry page 6 not 9
 14 February 2013 03:24 PM
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OMS

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Originally posted by: Mattysmith1983

Thanks for this OMS - My spec specifically asks for Split metered DB's but as always they think they can do without them and save a penny or too.


For sure, it's the game we play - enforce the spec is the only way to do it - refusal of a stage payment often helps focus the mind as well

Regards

OMS

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Failure is always an option
 14 February 2013 03:55 PM
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OMS

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Originally posted by: Mattysmith1983

Another question in TM39 :2009 it highlights on page 9 under the New buildings: Part L Compliance - Metering of lighting for new and existing buildings (to record the lighting energy consumption) should meet the minimum standards in table 49. Does anyone know where this table 49 exists? Is not in the TM or Part L documentation.


Didn't it become table 46 in the non domestic building services compliance guide 2010?

OMS

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 14 February 2013 04:53 PM
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Mattysmith1983

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Looking at he non domestic building services compliance guide 2010 i would say your right. It's seems relate to the TM reference.
 14 February 2013 05:01 PM
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OMS

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I think the table number chaged when the non dom was published - which was after TM39 was published, hence the error - it was table 49 in the consultation document.

I guess that gives you the answer you want however - if your contractors are not "metering" lighting in one of the 3 methods described then they can't claim compliance with Part L (and presumably are in breach of the contract conditions)

regards

OMS

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 14 February 2013 09:34 PM
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Parsley

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Good luck getting the building log book from the contractor!
 15 February 2013 09:09 AM
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OMS

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Originally posted by: Parsley

Good luck getting the building log book from the contractor!


No drama - we use a firm that does an excellent job of them - if the contractor doesn't provide it by due date, we simply advise the client to deduct a healthy sum including a management cost and point him to the right firm to get them done.

Same with O&M's, H&S files, "as installed" drawings and all the other stuff that contractors price for and don't do well (or at all).

Often the threat of doing so serves to focus a few minds - that coupled with a refusal to award practical completion and the pressure the principal contractor brings to bear as a result changes attitudes quite quickly.

Which is generally why we still can't get away from the adverserial approach in construction - even the best of projects gradually spiral down into a morass of claim and counter claim with every party entrenching thier position as the weeks go by - good news if you're a construction lawyer - bloody horrid time for everyone else.

Regards

OMS

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Failure is always an option
 15 February 2013 09:41 AM
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Parsley

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I like your style OMS
 15 February 2013 10:19 AM
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OMS

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Well, it's not really "my style" - I'd rather work with the contractor to resolve the problem of why/how this stuff isn't being produced - a quick chat and a few contacts they may wish to go to, often cures the problem.

On the other hand, when faced with some clown of a contracts manager who is determined to do things his way, then coversation and dialogue have to stop and the big stick comes out. If it's a contract requirement because not having the relevant documents ends up with the employer being in breach of several duties, then my duty is to my client - and we act accordingly. The extra effort on my part creates an additional fee which is due from my client - removing the said sum from the contractor is easy peasy - and it's often a big enough sum to hurt.

Construction - you've just got to love it

Regards

OMS

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Failure is always an option
 15 February 2013 06:48 PM
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Parsley

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Originally posted by: OMS

Well, it's not really "my style" - I'd rather work with the contractor to resolve the problem of why/how this stuff isn't being produced - a quick chat and a few contacts they may wish to go to, often cures the problem.



On the other hand, when faced with some clown of a contracts manager who is determined to do things his way, then coversation and dialogue have to stop and the big stick comes out. If it's a contract requirement because not having the relevant documents ends up with the employer being in breach of several duties, then my duty is to my client - and we act accordingly. The extra effort on my part creates an additional fee which is due from my client - removing the said sum from the contractor is easy peasy - and it's often a big enough sum to hurt.



Construction - you've just got to love it [IMG][/IMG]


Regards

OMS


Collaborative working

Regards

Edited: 15 February 2013 at 06:56 PM by Parsley
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