Applying metal roof paint these days is generally a simple task if you have the right equipment and know-how. There are also some specially formulated good quality long lasting acrylic roof coatings available that can be easily brushed, rolled or sprayed onto new metal roofing without a primer, although it may be necessary to ensure new roofing has properly “weathered” before the paint is applied. Generally, a roof that has been “weathered” will help the paint to adhere and bond better than a shiny new metallic roof. If unsure it is suggested you seek professional advice.