The urgent need for a boost to house building in the UK is obvious - indeed, it has become one of the central issues in the general election campaign.

But if the recovery in the industry is to continue (and it has been recovering well in recent months, albeit from a low base) more action is needed to tackle the skills shortage at the heart of the trade.

The industry has been talking about the problem for many months, with construction firms starting to warn last summer that they were struggling to find the staff they need and that a lack of suitable workers could restrict expansion. It is a warning that has now been repeated by the Federation of Master Builders Scotland, whose director Gordon Nelson says attracting skilled workers has become a chronic issue.

Mr Gordon says the first three months of the year have been generally positive for the industry, with workloads and enquires on the rise, but that there is still a severe shortage of staff, particularly carpenters, joiners and plumbers. Migrant labour is helping to fix the problem to some extent, and provided that does not help to suppress pay and conditions, that is a solution in the short term. But longer term, the construction sector needs to attract new recruits, particularly the next generation of apprentices.

There has already been some improvement. The number of building apprentices registered in Scotland rose by seven per cent to 1,553 last year, which is 20 per cent higher than 2012, but there is still a long way to go before we get anywhere near their pre-recession levels when there were around 2,700 building apprentices. What has made the problem more acute is that the rapid contraction in the industry saw large numbers of experienced workers drifting away in search of other work, many of them never to return.

Both construction firms and politicians must contribute to fixing the problem. As Mr Gordon concedes, the industry needs to refocus and address the long-term decline in traditional apprenticeships by attracting new entrants and that must mean investment in launching and expanding apprenticeship schemes, and for smaller firms that could include pooling resources in some cases and sharing apprentices.

But government has a role too. The Scottish Government has plans for thousands of new apprentices in a range of fields and a strategy to forge closer links between schools, colleges and employers, but it has also driven through college mergers and presided over cuts to grants for the poorest students and the full consequences of those decisions are still to be seen. To its credit, Labour says it would seek to reverse this and invest £100million more in Scottish colleges to help increase the number of places.

As for the Conservatives, there are worrying signs in their message on apprentices, which appear to demonstrate a profound misunderstanding of what an apprenticeship should be. Employing an apprentice means investing in the future of someone who can give something back in years to come, but the Prime Minister is talking about forcing people into "apprenticeships" as a means of getting them off benefits.

That is not the way to go for the building industry, or any industry. Apprenticeships should never be just another way to access cheap labour. With proper investment from building firms and government, they could be a way to accelerate and deepen the recovery.