To see a short video of how the windows are being installed <a title="Window installation" href="https://www.dropbox.com/sc/ske0gjxh3p9ldqa/OkXi_v0O4i" target="_blank">go here...</a>

Note the builders are not wearing hard hats, are riding on a pallet without guard rails or restraints. At the end of the video they bump into the newly laid tiles and crack one so at that point I stopped videoing and walked away.