In fact as far as i can recall no house i have ever inspected has ever had all of the following in place.
No water in tank in attic.
Some attic expansion tanks were intended to be drained manually if needed and may not be piped to a drain.
More pipes and connections a least five for an attic tank.
A hot water tank such as a range boiler would have water coming in from a boiler or supply water going out to plumbing possibly heating by gravity or convection.
A system boiler takes its water from the mains and will heat the water for your radiators but not your taps.
A tight fitting lid on the water tank.
Fully lagged pipe work again to.
Overflow from attic expansion tanks that are open to atmospheric pressure typically run outside to a roof gutter and drain system risking freezing and blockage in some climates or the tank may be connected to a building drain.
If the builder has already installed your water heater in the attic you can get it moved to another location in the house or into the garage.
Another option is to choose a tankless water heaterto be installed in your attic.
A fully insulated tank with the base exposed to a part of the attic floor which has been left un insulated to allow the.
To be able to remove the water tank from the loft and receive water at mains pressure you will need to replace the boiler with a system or a combi boiler.
This is far less expensive than your water heater leaking and causing thousands of dollars worth of water damage.