Having watched them erect a multistorey car park in Welwyn Garden City, I'm not surprised. And I wouldn't go in it once it was open, either.
They built the pillars to the finished height, then laid the floors one on top of another on the ground, with release agent between them, waited for the whole lot to set, then put hydraulic motors on the tops of the pillars and lifted the floors into place. Better hope the bolts holding the floors onto the pillars don't corrode ...