Germany and the USA are the most productive manufacturing economies in the world with the most productive workers because they don't have lots of cheap labour making things. Their businesses, especially their SME's, are far more capital intensive than ours. The efficient use of capital, more than the efficient use of labour, reduces costs.
The last thing an efficient construction sector needs is lots of cheap labour. Anyone using a hand saw or hammer on a building site should be sacked. There should be no need for block or brick laying above the groundworks level. There should be no first fix on site. There should be no door hanging on site. There should be no roof tiling on site. The way we build houses is Dickensian. The entire sector is not fit for purpose and, speaking as an Irish Tradesperson, Irish Tradespeople are not at the races when compared to the European competition. Eastern European tradespeople are generally smarter, much better trained and have a vastly superior work ethic.
Hopefully we'll eventually get to the stage where 80% of the construction of houses is done in factories, here or elsewhere, and 50% of the labour disappears.