THERE'S been a great deal talk about under-occupancy over the past two years, and generally it's been linked to talk of under-occupants - social housing tenants who have more bedrooms than they apparently need.

But what about those who don't occupy their properties at all? At the last count, more than 31,000 homes in Scotland had been unoccupied for six months or more; a significant number at a time of chronic housing shortages.

The issue has been brought vividly to life (or should that be living death?) by John Maher, the former Buzzcocks drummer who moved from Manchester to Harris after retiring from music and now works as a photographer. His haunting images of abandoned homes in the Western Isles were the catalyst for a new project that will transform an empty island property into an eco-friendly demonstration home. The hope is that a successful transformation will encourage more investment and bring more of the isles' abandoned properties - which number an astonishing 1,000 - back into use.

Many abandoned island homes are former crofts that are derelict beyond saving, or too remote to be worth the cost, but across Scotland work to bring more conventional empty homes into use is picking up pace. The Scottish Empty Homes Partnership began in 2010 and, while its first three years of results were decidedly unimpressive with fewer than 200 properties brought back into use, the figure for 2013/14 was 278, and for the year just gone more than 500. Clearly, there is more to be done, and the Scottish Government has given the partnership funding for a further three years. But is this enough?

Staff from housing charity Shelter have been working with local authorities, half of which have a dedicated Empty Homes Officer. Work with neglectful homeowners falls into four broad categories: advice signposting, negotiation, incentives and enforcement. Three carrots and one stick, which perhaps helps explain the slow progress. Compare this with the single-stick approach the UK Government has taken to solving the problem of social housing under-occupancy: cutting the housing benefit of those affected even if there is nowhere smaller for them to go. Perhaps, if Scotland wants to prove its social justice credentials, those wealthy enough to have entire spare homes should be given a similar shove, rather than a series of gentle nudges.

One way of doing this is to hike up council tax rates for empty properties, and local authorities were given the power to double them in 2013, a change that no doubt helps explain the recent spike in figures. However, not all councils have used the power, and indeed some still offer a discount for empty homes that lasts beyond the first year. Glasgow City Council gives 10 per cent off for unoccupied properties, a far cry from the 100 per cent increase introduced in Edinburgh and elsewhere. Some will, of course, argue that a discount is fair and an increase outrageous - after all, unoccupied homes don't have bins that need emptied - but is it morally defensible to let a viable dwelling lie empty when homes are scarce?

Who are these people who can afford to pay 90 per cent council tax on a home where no-one lives, let alone 200 per cent? I'd wager many of them have inherited these "bonus" properties, often without paying a penny of tax in the process. Shelter estimates that leaving a home empty can "cost" up to £7,000 a year - but that figure includes hypothetical lost rental income so the real outlay for council tax, security and repairs will be considerably lower. The key question is whether this cost is likely to outweigh any increase in the property's value, as the housing bubble inflates again and those sitting on assets they haven't earned look forward to cashing in their chips. Meanwhile, regular working people with just the one home (which they can't sell unless they buy another) illogically rub their hands at the prospect of "gains" they'll never see, endorsing policies that push home ownership out of the reach of their children and grandchildren - at least until such time as they shuffle off their mortal coil and leave a free house.

Scotland may not, for now, have powers over inheritance tax, but it does now have extra mechanisms it can use to strong-arm those who put personal profit above common good. It's just a matter of using them.