Do I need to prime recently painted doors again?

[casademont]

I painted some doors in Dulux Quick Dry Satinwood (water based) about 12 months ago. Prepped well (sanding, primer, etc) and they came up really nice. I did 1 coat acrylic primer, 2 coats top.

Since then we had some unexpected building work done, and they are all dirty enough to require repainting. Do I need to prime with an undercoat again, or can I just soap and sand them down and add another layer of Satinwood finish?

Thanks!

 

[opps]

You don't need undercoat provided that you "key" the paint first.

To reduce the risk of accidentally cutting through the existing layers of paint, I would recommend a light rub down with 180 grit silicone carbide paper (the grey stuff, rather than aluminium oxide- which will normally be white, yellow or red).