relocating

I will be relocating to California on a L1B visa initially and then
an employer sponsored green card visa. Since I will only have
worked in Ireland for half the year will I be owed tax back ?

Also, I bought a house a year ago and was exempt from stamp
duty. I think I remember reading that if a person moved abroad
they would not be liable for a stamp duty clawback ? Would I
be able to rent a room out up to the limit while I'm away ?

In general, the rent-a-room scheme only applies to landlords who live in the property being rented. I understand there are some more general exemptions on income tax and CGT for those who are relocated by their employer, but I'm not familiar with the details of these. Hopefully, other posters will be able to help. Is your current employer moving you to the US?

correct, the L1B visa is an internal transfer within the company I work for
and I have worked for them in Ireland for 2 1/2 years. Do you know what
the stuation with income tax is ? will I be entitled to something back ?

Is this topic of any use to you?