How can I repaint my weatherboards?

My weatherboards are painted in dark red coloured water based paint, which is about seven years old, and I want to repaint them in a cream colour. Do I need an undercoat or can I apply two coats of a cream colour directly onto the existing paint.

We would recommend the walls be washed with sugar soap first, then apply one coat of British Paints PREP 4 in 1 (water based), tinted to TU1, and then apply two coats of British Paints 4 Seasons tinted to your preferred colour. Please refer to Bunnings Team members for guidance.