When your father left you the house in 2009, you were then liable to inheritance tax but only if the value of that inheritance when added to other gifts/inheritances from your parents exceeded the threshold. The threshold applicable for 2009 depends on when your father died. If he died between the 1st of January and 7th of April, your individual threshold was €542,544. If he died after 7th April, the threshold amount was €434,000.
So, if you and your brother hadn't any other inheritances/gifts from your parents and the house was worth less then €868,000 when you inherited it, then there was no inheritance tax due.
When you sell it now, you will be subject to Capital Gains Tax, at 30%, if the amount the house sells for is more than it was worth on the day your father died. Given the way the property market has gone, this is unlikely. It is more likely that you will make a capital loss which you can use against other capital gains you make this year or in the future.