Three Phase Supply for New build House

[breezer]

ive worked in a "gym" the forum plumbing boys would have loved it, about 4 big "hot water cylinders" each must have been 8 foot tall and about 5 feet across, cant remeber the number of boilers and pumps.

point is it was all gas heated hotwater

 

[equitum]

Thanks for replies, but sounds as either :

a) few on forum have experience of providing a design/estimate for such an installation with a limited brief,

b) my scenario and assumptions are incorrect or too vague


..but I suspect this is not an unfamiliar situation, i.e. large house with modern requirements for excessive lighting, plentiful appliances and therefore socket outlets, other circuits, along with multiple electric showers.
I will consult the DNO (as was my intention) and maybe share the outcome on the forum.

 

[Steve]

I know as the electrician you have no input, but WHY are people still designing houses with downlighters????? I get the feeling they are seen by some as low energy, especially low voltage, the word "low" being the key factor here.

 

[equitum]

Yes, it is vague, but so is the criteria I am furnished with to provide an estimate.

DIY?

Please explain ricicle

 

[Adam_151]

Get some estimates off the DNO, you'd probably manage with 100A SP, but to give more leeway see what the difference would be for 100A on 3P

Not sure about the CU on each floor, 3 Phase DB somewhere on the ground floor might be better, 8 way should do it, 12 if you want to be sure there is more than enough room to expand.

Whats the floor layout, would be nice if you could have the meter cabinet backing onto something that could be used as a switchroom, not a cupboard as it'll get filled with junk, perhaps a utility room?

 

[Steve]

IIRC, YEDL dont charge much more on a new supply to have 3 phase over single phase.

 

[plugwash]

Which would make sense. Afaict most of the cost is the labour which doesn't increase significantly with the addition of a couple of extra cores.

 

[Steve]

Sorry, its CE electric now.

 

[ricicle]

Yes, it is vague, but so is the criteria I am furnished with to provide an estimate.

DIY?

Please explain ricicle

You seemed to me to be getting annoyed with the answers given, which seems a bit off to me seeing as it appears you are doing this job for money ie not diy.

 

[equitum]

Yes, it is vague, but so is the criteria I am furnished with to provide an estimate.

DIY?

Please explain ricicle

You seemed to me to be getting annoyed with the answers given, which seems a bit off to me seeing as it appears you are doing this job for money ie not diy.

Ah I see, fair point, though other than one post that was apparently intended as humurous (and for some reason the author has subsequently decided to withdraw) I have been thankful for the replies given so far.

Yes this job is potentially for money and therefore not DIY, but I was unaware that such posts were frowned upon, especially as they are quite common on the site. Furthermore I and I am sure others, learn and take interest from other posts, DIY or not (no pun intended).

Indeed there may be a forum DIY'er undertaking a self build and may be contemplating the wiring of a similar property his/herself.

 

[Pensdown]

In my experience the number of bedrooms & bathrooms is a red herring when it comes to domestic loadings.

I would be very surprised if your self builder will want electric showers in the main bathrooms so for design purposes I would allow for a few in the guests on-suites. These probably won’t be used very often so they could almost be ignored in your maximum demand calculations.

You need to speak with the lighting consultant because although he has specified 150 luminaires you need to know what type. I read an article about a 6 bedroom house in London which has just been built. By using LED’s for decorative lighting and CPF elsewhere the total lighting load for the whole house is around 350watts! Although you can’t dim CPF when you’re designing a new build you can be very creative with the switching to achieve the same mood effects. This also applies to other forms of lighting so you can’t assume anything.

As for the rest of the house the loading will probably be the same as the average 3 bedroom semi with 6 people living in it.

IMO a 100amp SP&N supply is more than adequate based on the information you have.

PS..Don't forget that there is a trade forum for these types of post

 

[equitum]

Thanks, good points.