 In 1952, Andersen began fitting its windows with a first-of-its-kind Welded Insulating Glass to provide protection against condensation and frost.In 1957, an Andersen advertisement in the trade press was titled "A Fervent Plea for the Letter E" because journalists misspelled the name with an 'o'..The Perma-Shield cladding system made its debut in 1966.The patented vinyl exterior for wood windows was developed with the help of Italian inventor Luigi Zanini.