The cost of retrofitting the roof of a property to remove the anechoic dome is about $10,000 per square metre, with the roof installed at the cost a third of the cost.

The cost to replace the awners, as well as replacing the existing ceiling, is also high.

“We estimate that in terms of retrofit costs, about one-third of that amount would be paid for by the taxpayer, while the other third would be covered by the property tax,” the Land Revenue Authority said.

The authority said that the cost to retrofit the aero roofs was $40,000.

“The average cost per square foot of an existing roof is about £100, but if you are looking at the retrofit, it could be up to double that,” the authority said.

A spokesperson for the Government said that, as with the cost for retrofitting a house, the cost would be borne by taxpayers.

“As part of the package for retrofit and maintenance, there will be a contribution from the taxpayer,” the spokesperson said.

“If the cost is not covered by taxpayers, the amount is passed onto the property owner.”

The spokesperson added that the Government would not support any form of retroactive tax, including the one currently in place.

“That would be a breach of the Tax Acts,” the spokesman said.

The spokesperson said that although retrofitting is a “common sense” solution, the Government does not believe it is the best way to address the cost and complexity of aero retrofits.

“The cost to install aero-resisting awned roofs is higher than most of the other options available for retrofits, and the cost associated with aero removal is higher,” the spokeswoman said.