Granny flat and shared rainwater tank. How electricity/water usage is divided?

Hi,

I have a brand new IP in NSW that has main house + attached granny flat.
Granny flat has completely separate electricity meter and water sub-meter.

The toilets, laundry and garden tap for both houses are connected to a common rainwater tank which consumes electricity + water from main house only.

Granny flat and main house are rented to two separate tenants and there is no special clause about the shared bills as tenants believe they are paying for their own usage.

it's been only 2 months since the property is rented. Tenants have not complained but I guess they don't know about the rainwater usage yet.

How can I sort it out so both tenants get a fair deal? Few options I can think of:

1. propose to introduce a new clause in main house lease now that states how rainwater tank is used. (would tenant agree without fuss?)
2. Get my own plumber in and have toilet, laundry, garden tap of granny flat disconnected from rainwater tank and connect to granny mains. is this possible without incurring huge cost? Am I violating any BASIX guidelines?
3. Give main house tenant discount in rent. (How much?)
4. Do nothing.

I believe, the usage in terms of $$ is very low. But it's not fair on main house tenant's part to pay for Granny flat rainwater tank usage.

What is the best way to go about solving this problem?

 

What does this mean? The rainwater tank uses power and water?

 

Yes. Rainwater has a pump system which runs on electricity (I can see it is plugged to electric socket). I believe once water level in the tank goes below a mark it switches to mains water. Hence it usage mains water as well.

This is as per my understanding on the working of rainwater tank. Unless I am missing something.

 

I pretty much know next to nothing about rainwater tanks, but I'm surprised yours works like that. It seems to beat the whole point of a rainwater tank if it uses power AND just spits out mains water half the time as well.

I'd want to go for a proper long term solution and change up the rainwater tank somehow (or decommission it entirely).

I wouldn't just do nothing.

 

It may be illegal to do so. This may violate BASIX compliance.

 

Is both the house and the granny a completely new build? If so, and both need the tank for basix, you could just put in a small tank for the granny flat.

Are you sure you are allowed to rent the granny flat out to a party unrelated to the main house tenants?

I ask, because in a new build I would have expected metering to be completely separate.

 

First step is to check tenancy regulations in your state.
These may prohibit passing on usage charges unless completely separate meters.
Or may have a formula to apportion.
Marg

 

I'm no expert in rainwater tanks, but I do know that a lot of them have pumps.

The water is generally collected on the roof of the house, then flows down into the tank. From there it's on about the same level as the actual outlets that use it, so it needs a pump to deliver it to the tap with a usable amount of pressure. Alternately some tanks are raised, but then you need to pump it up into the tank from the roof.

My parents migrated north for the winter a few years ago, as they do. They live in Ballarat where it can get quite cold. Dad left the pump on. The pipes froze, split, then thawed. The pump then proceeded to push about half a swimming pool of water from two very large tanks through the house.

They only discovered the flood several weeks after it occurred and the entire house needed a major renovation. Insurance paid for the lot (about $150k) as well as accommodation for the next 12 months. They're actually looking at the whole event as a huge win!

 

This is one of those things that will never be an issue until the tenants are annoyed about something and look for something else to complain about. I think you're doing the right thing by being proactive, though it's a shame you didn't pick this up before it was constructed. I would think that any changes are going to be irritatingly expensive. Is this type of set-up particularly common? It seems a bit of a strange oversight for an investment property.

Practical solutions:
1. Disconnect granny flat from tank water completely. (Cheapest solution, but does it violate BASIX? I'm not too familiar with it.)
2. Install smaller tank to granny flat with same set-up.
3. Ignore.

I don't think the discount is practical, nor is trying to control how the water is used. The issue here is not really the minuscule amount of water and power that the auxiliary dwelling will use from the main dwelling, it's more so the fact that there is technically an element of shared 'metering' which someone might try to use against you down the track.