"The construction has twenty floors."

Translation: A construção tem vinte andares.

[chicca63]

Is it correct to say O edificio? OK, literally it would mean "building" but ...

[Paulenrique]

I think duo prefers more literal translations.... the translation for building is edifício, prédio . In my region we normally use prédio ;)

[Danikalifornia]

Is it ok to use "pisos"?

[Paulenrique]

No. We usually say "andares". We say "piso" when you are already inside the building or to refer to its inside, ex: consultório do dentista é no segundo piso/andar. Moro no quinto piso/andar. Inside the building you may also find signs indicating where you are using the word piso: primeiro/segundo/terceiro.... piso/andar. Hope you got it :)

[MaynardHogg]

English refers to buildings as "constructions" only during their, ahem, construction.