I understand that the "conversion" the Deputy is referring to is from industrial or commercial (i.e. non-residential) use into residential use.
In Budget 2018, I increased the rate of stamp duty on the purchase of non-residential land and buildings from 2% to 6% while leaving the rate of duty on residential buildings at 2%. I also introduced a related measure intended to further incentivise the supply of housing in Section 61 of the subsequent Finance Act (Finance Act 2017). This scheme provides that land chargeable at the 6% rate on its acquisition and subsequently developed for residential purposes can qualify for a refund of the difference between the 6% and 2% rates, subject to certain conditions designed to ensure that the land is optimally utilised to deliver residential property within a reasonable timeframe.
This applies to the development of single one-off houses as well as to multi-unit developments.
I can confirm that the introduction of any other such tax reliefs is not currently being considered by my Department.