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23 Feb 11 8:27 PM

I'd guess the building company has assigned you a project manager, well he should manage the project and inform you of any changes! Are you a builder ... Pre line inspection? What exactly as the custo......read more

23 Feb 11 6:14 PM

Your being had!! Due to pressure? An extra three meters would make no diffence.. Pressure ddiesnt change with distance between 40 and 43 m, get them to move to original location as the plans you signe......read more

27 Jan 11 6:17 AM

Hi dejan, Did you import the windows yourself? Can I ask what German brand of window? I am building a house and would be interested in finding a decent supply of efficient windows. Cheers matt...read more

28 Aug 10 7:19 PM

Hi, thanks for everyones 10cents. the guys from kipping heat have been very helpful. The only question I have is the COP of heat pumps. If I want to compare apples with apples I need to know the avera......read more

18 Aug 10 9:26 PM

Thanks a lot for all your feedback, It is really useful, I agree $35k is absolutely crazy money but I have five quotes from company's in Christchurch and all of them come within 3 or four thousand of ......read more

17 Aug 10 10:44 PM

am building a 285m2 house and are struggling with how to heat it. I wanted to use Heat Pump Hydronic underfloor heating but have been suggested electric underfloor by the architect. The house is a s......read more

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Member Profile: Buntar

Underfloor heating. electric versus heatpump

17 Aug 10 10:26 PM

I am building a 285m2 house and are struggling with how to heat it.
I wanted to use Heat Pump Hydronic underfloor heating but have been suggested electric underfloor by the architect.

The house is a solar passive design with r5.5 insulation in walls and ceiling and thermally broken aluminium. Living areas are all exposed concrete floors and bedrooms carpeted

My issue is with a underfloor heat pump system quotes are all over $35,000. to get the most COP from these systems i t would run during the day when electricity price is 25c a Kwh

A underfloor electric system is only $5000 and would run on night rate only at 10c Kwh.
In the sth island our night rate kicks in at 9pm.

Therefore if I compare the heat pump running on day rate it needs a COP of 2.5 just to match electric underfloor running on night rate.

The average yearly temp in CHC is 13deg according to the met service

We are spending a lot of money reducing the heating load of this house and i am loath to spend upwards of $30,000 on a system i have spent a lot of money to reduce the need for.

Electric underfloor leaves upwards of $25000 in my pocket...this buys a lot of electricity/windmills.

Any advice or experience would be appreciated.

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