A construction industry without foreign labour is about as viable as a fish on a skiing holiday. So in the midst of the political hoo-ha over immigration, one thing is clear.

Without the open-door policy for Poles, many sites across the UK would have ground to a halt by now. More than 13,000 Polish construction workers, not counting the legions of self-employed, are among the 600,000 people who are thought to have arrived in the UK from the eastern and central European countries that joined the European Union in 2004.

This is the biggest wave of immigration to Britain for three centuries. It has stocked projects with skilled tradespeople, and in the process it has stopped the economy from overheating by keeping down wages and therefore tender prices. An RICS survey found that eastern European labour had allowed three out of four firms to hold down the wages of manual workers, and that one in three believed professional salaries had been suppressed for the same reason.

Indeed it’s unlikely that the industry would be experiencing its current upturn in orders had tender prices gone skywards, which at one point looked possible. So for construction, the EU expansion – which has (let’s face it) legalised the employment of eastern Europeans and hopefully weakened the black economy – must be judged a success.

The economic outlook in the longer term looks brighter, too, with forecasts showing growth of 8-10% all the way to 2008. The last thing the industry needs now is for the government to restrict its access to skilled labour. That’s not to say the industry would be vehemently against some degree of controls for Bulgarians and Romanians if their countries join the EU next year. Indeed, the points system that is currently being proposed would satisfy the needs of the sector if it accurately reflected the state of labour market.

That said, a migrant workforce brings heightened problems with safety. The main danger appears to be workers who don’t speak English, and therefore can’t understand warnings. The experience so far is that workers are most at risk during their first month on site. Given the value of their work to the industry, shouldn’t employers be looking for a way to protect them during this vulnerable period? The least they can do is provide safety booklets in Polish and pair Poles that don’t speak English with ones that do – but how about helping to pay for language classes before a worker starts on site?