Yet another maximumdemand question.

[Spikenaylor]

Hi there.
I am struggleing with working out maximum demand for the following.

Large house, ground floor, 1st floor, 2nd floor(study/office and storeroom)

Grnd floor sockets ring (32A)
1st floor sockets ring (32A)
2nd floor sockets ring (32A)
grnd floor lights (10 lamps) (6A)
1st floor lights (9 lamps plus ceiling fan and bathroom extractor) (10A)
2nd floor lights (5 lamps + bathroom extractor + 12 led recessed ceiling lights) (6A)
Kitchen sockects radial (20A)
Kitchen utility sockets radial (dishwasher, fridge) (16A)
Hob (45A)
Twin double ovens (45A) eg Neff U16E74 total connected load 6.8KW *2 = 13.6KW probably wont go for these, but they havent decieded yet she is a cake baker by trade.
Kitchen lights (6A)
Utility room sockets radial (32A)
Fridge Freezer Large (16A) RCBO
Immersion Tank (16A)
Central heating system and pumped Shower (20A)
Underfloor heating bathroom and kitchen (20A)
Smoke and heat alarm system (6A)
House alarm (6A)
CCTV (6A)
Outside light network (10A)

Client wants all the seperate circuits, not sure on underfloor wattage or pumped shower rating yet.

just struggling with working out what to use for max demand in this scenario.
any advice greatly received.
any advice on CB ratings for the above helpful.

Many thanks
Spikenaylor

 

[GT1]

Well I would start with all the large loads. ie heating. That's water heating, cookers, underfloor, etc.
Your RFCs would be next for consideration.
Even with just those two you may be getting close to needing another phase from DNO.
I would question the demand against the fridge tho.. even a big'gun...!

 

[GT1]

You have 20amps for central heating and pumped shower ? Also seems high assuming gas boiler.

Is the underfloor heating pumped hot water or electric..?
Likewise you have it at 20amps. If its pumped water it wont need anything like that.

Apply diversity to get the numbers more realistic for your demand.

 

[telectrix]

think of a figure. double it. then divide by the first figure. the answer is 2.

 

[micknew]

Maximum demand of 20KVA, 100A service fuse.
Thats what we request from the supply company.