That's not how productivity works. It's not a zero-sum game.
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.
See the increase in CEO wages vs the increase in worker wages over the last 20 years of you want to know where that 5% will almost always go.
Why would the company pay more when they can just not pay more? The only things I can see happening is they might lower prices as competition ramps up, or in general as there is more supply for the same cost.