Imposing a tax on buildings makes no sense

The mansion tax is a tax on an asset rather than labour so in that respect it is similar to a land tax. However the important difference is that land ownership is equally inconvenient to us whether or not there is a house on it. We are penalising something which has no negative impact on other people.

A land value tax on the other hand makes more sense because we are indifferent to whether there is a house on the land... in either case we have no right of access. Land ownership is a cost to everyone but the property owner. For this reason it makes sense to impose a tax on land not on buildings.

The land value ceiling: an explanation of how it works

The land value ceiling is a limit imposed by the government on personal land ownership. Under this rule no individual is able to own an amount of land in excess of the land value ceiling. Anyone violating this rule by owning an excess of land will be asked to either give it away or to sell the land. If they do not do so measures will be taken to bring them into line including the possibility of the land being confiscated.

It is a quantity of land measured in market value not the physical area of the land.

There is nothing wrong with a land value ceiling

There is nothing wrong with a land value ceiling because land is finite.