Do we pay capital gains if we can't sell in 12 months?

I know that people selling their homes have a sort of "grace period" after which they will have to pay Capital Gains Tax on the sale.

In my situation, my house has been on the market for 10 months now - if it doesn't sell within the year do I have to pay CGT? Just to be clear, this house is not an investment, it was our home and we have traded up to another house. Also we have not rented it, it has been vacant throughout this time.

AThe last 12 months of ownership is regarded by Revenue for Capital Gains purposes as a period of occupation - which essentially means you have 12 months to sell your home before you incur a Capital Gains Tax liability.

It's not something that sellers thought twice about during the property boom when houses sold almost as soon as they went on the market, however things are more than a bit different now and it is taking considerably longer for property to sell.

So if it goes over the year mark, then yes, you will have to pay Capital Gains Tax although it is calculated on a proportional basis.

So if, for example, the house sold 14 months after it ceased to be your main residence, then you would be taxed on the equivalent to two months worth of gain or, as the Revenue explains: Mary purchases a house on January 1st, 2000 and occupies it as her main residence until December 31st, 2005. She sells it on June 30th, 2007. The exempt proportion of the gain is 14/15 months which refers to the actual period of occupancy (six years) and final 12 months which equals seven years out of 7.5 years of ownership. The balance of the gain, i.e. 1/15th (which equates to six months of ownership) will incur Capital Gains Tax.

How can we check for radon gas?

There was a terrifying report in your paper last week urging homeowners to "check for cancer causing gas, radon" and saying that houses in the south-east and west are particularly affected. As we live in Waterford this has caused us great worry but the article didn't mention how to check for radon.

AThat report was in connection with a house in Tipperary where the level of radon recorded was a massive 45 times the acceptable level - the problem has since been addressed with a radon sump. Dr Tony Colgan of the Radiological Protection Institute of Ireland (RPII) has asked householders to test their homes because 91,000 homes in Ireland have high radon levels, but only 4,000 have been identified so far. The good news is that it is a non-invasive, inexpensive (E56) test and there are a range of measures, some very simple (ventilation), that can be taken to sort out a radon issue. The test does take a little commitment from the homeowner as two small radon detectors need to be placed in the home for three months and then sent back to the RPII for analysis.

It's an efficient service and well worth the peace of mind. Contact the RPII, Radiological Protection Institute of Ireland (RPII), 3 Clonskeagh Square, Dublin 14. Tel: 01-269 77 66, or www.rppi.ie/radon

Your questions:

Send your queries to Property questions, The Irish Times, The Irish Times Building, 24-28 Tara Street, Dublin 2 or email propertyquestions@irish-times.ie. Unfortunately it is not possible to respond to all questions. The above is a representative sample of queries received. This column is a readers' service and is not intended to replace professional advice. No individual correspondence will be entered into.