Ondura is made of a tough organic fiber core that's impregnated with asphalt, a natural preservative. Thus it will never rust or corrode like metal does. That's why Ondura is backed by the strongest warranty in the roofing industry.
ONDURA CAN BE INSTALLED DIRECTLY OVER OLD RUSTY METAL ROOFS...SAVING TEAR-OFF EXPENSES
As you can see with the photo at the right, Ondura can easily be installed over old rusted metal without incurring expenses for tear-off. You'll never have to deal with rusty roofs again.