If all construction workers can build houses 5% more efficiently, that's not the same as nothing changing. Depending on supply and demand, it means 5% more houses are built, or houses are 5% cheaper, or maybe 5% bigger, or some combination. Whether or not the construction workers all get a raise or 5% get fired (or both) depends on that supply and demand, but historically they often get a piece of the growing economic pie.
So you're right in an academic sense, but not for any practical purpose whatsoever, in terms of how it'll affect economy now.
To try and explain one path: Company A doesn't raise wages but makes 5% more money. Company B pivots from Industry B into construction (because suddenly construction is having 5% fatter margins), and hires workers at more competitive wages to poach them from Company A. Company A forces to raise wages.
If there's a demand ceiling on housing it's a different story though.