Power calculations
Question from Kalisi updated on 31st January 2017:
The property manager advised me that there is one power bill which she will divide between me and the sleep out at the back based on meter readings.
I was ok with this until I started receiving my share of the power bill and I noticed discrepancies in the billing dates and calculations.
Now I don't have any confidence in the calculation system the property manager is using.
On what grounds can I get them to separate the power supply so that I can pay my own power?
Our expert Bernard Parker responded:

Sharing one power account between two properties is not uncommon in situations like yours where a tenant is renting a sleepout or flat on the same property as a larger house. Often a landlord will rely on an agreement between the occupants of the two properties about how to split the electricity bill when it comes.
The difficulty comes when one tenant is not happy about the method of calculating the usage. Over winter, especially, one can think that the other is using more power on heating or cooking. Also, when one goes away for a week or two, the usage is unbalanced.
You should not be expected to pay for electricity supply that you do not use. You can expect to pay for the utilities that you use (such as electricity, gas and, in some areas, water). But it is usual for a meter to record the amount of electricity you use.
Installation of a separate electricity supply to the sleepout is possibly more expensive than the landlord wants to pay, and the splitting of the account by some agreed formula is seen as the cheapest option.
When the sharing of the account seems to be unfair or unbalanced, the best solution is to have a means of recording your actual usage. A common solution is to have a check meter installed. This is fitted into the cable that goes from the main control board to your sleepout, and it records your usage. It’s a lot less expensive to install than a separate feed from the supplier, and it allows you and your property manager to calculate your usage accurately.
You will possibly have to pay a proportionate share of the monthly “line charge” that the supply company charges, but this can be identified and agreed. Then your actual consumption will be read from the check meter, and your consumption costs will be accurately calculated from the supplier’s published rates.
Bernard is principal of Quinovic – Kapiti-Mana. Quinovic's outstanding people and systems provide the most professional, effective and reliable residential property management service in the NZ market for over 30 years.