Jerome

Assembling, you shall make an ark, and you shall finish it with a cubit from above. As for the reason why it says, assembling, you shall make an ark, in Hebrew it has, 'you shall make the middle of the ark,' which Symmachus interpreted more clearly, saying 'transparent,' that is, making the ark clear, intending for a window to be understood.

Hebrew Questions on Genesis ↗

Bede

You shall make a window in the ark, and you shall finish it to a cubit from above. A window is commanded to be made in the ark so that, after the rains ceased and the ark rested, Noah might release a bird through it to ascertain whether the waters had ceased, or whether the earth had dried or sprouted, so that he also, having opened it, might see the light of the sky; hence in Hebrew it is aptly translated as having the noon, because windows are usually illuminated more clearly by the midday sun; which also aptly accords with …

Commentary on Genesis (Hexaemeron) ↗

Gregory of Elvira

That the ark, however, is referred to as having a second story and a third story evidently shows the places of the dwellings and the qualities of the habitations that are prepared for the saints in the kingdom of God. Indeed, in one story is a figure of paradise, in another of the new earth—where heavenly Jerusalem is to descend, so that there may be in it, just as it is written, the habitation of God among men; of which earth the blessed John says: And I saw a new heaven and a new earth and the heavenly city Jerusalem, descending …

On The Ark Of Noah 15-20 ↗