Viwinco Vs Andersen . Unlike most window manufacturers, which rely on partner companies to supply them with glass, milgard makes its own glass at its. Many additional aluminum, vinyl, and fiberglass windows and patio doors are available from the manufacturer. Andersen Double Hung Windows With Transom from www.mycoffeepot.org He delivered the windows and installed them. Both andersen windows and renewal by anderson might have the same manufacturer, but their warranties are not quite the same. Viwinco prices range from $40 to $75 per square foot for the windows themselves.