Painting exterior and interior window trims

[phiaxs]

Hi everyone!

I’m looking into repainting my exterior and interior window trims. I’ve been in this house for a few years and it’s time to get some work done on these trims. This is what they look like:

Exterior (painted but unsure if water or oil based)

Interior (water based stain)

I’d love your advice on what’s the best paint to use for durability and protection from uv and mould. The interior windows suffer from condensation during winter and there are signs of mould build up on the window sills. Should I use the approach of sanding 120 grit paper with a detail sander, Dulux 1 step water based primer and then Dulux aqua enamel for both exterior and interior? I’ve heard of Dulux weathershield and would like to know if that is a better option. Can I use a water based primer on the stain wood after a proper sanding?

My goal is to keep the window trims low maintenance and give it a more modern look with a darker brown, low sheen colour to it. 

 

[MitchellMc]

Welcome to the Bunnings Workshop community @phiaxs. It's brilliant to have you join us, and many thanks for your question about painting window trims.

Repainting your window trims is a great way to refresh their appearance and protect them from further wear and tear. To begin, prepare both the exterior and interior trims by sanding the surfaces with 180-grit sandpaper. This will help remove any deteriorated timber, flaking paint, or rough edges, creating a smooth base for the primer to adhere to. A detail sander is particularly useful for reaching tight corners and intricate areas. For the interior trims, which show signs of mould buildup, clean the surfaces thoroughly with a mould remover or a solution of vinegar and water, ensuring they are completely dry before moving forward.

For priming, it’s best to use either Dulux Oil-Based 1 Step Primer or Zinsser B-I-N Primer Sealer Stain Killer. Both options provide excellent adhesion and stain-blocking properties, especially on stained wood, and will prepare the surface for a long-lasting finish. Apply the primer evenly, allowing it to dry fully as per the manufacturer’s instructions. If you’re working with stained wood, these primers can be applied after proper sanding and will ensure the topcoat adheres well.

When choosing paint, durability and resistance to UV and mould are key considerations. For the exterior trims, Dulux Weathershield is an excellent option, as it’s designed to withstand harsh weather conditions and offers long-term UV protection. For the interior trims, Dulux Aquanamel is a suitable choice for its water-based formulation, which provides a modern, low-sheen finish and easier maintenance. Ensure that the topcoat is applied in thin, even layers, allowing adequate drying time between coats for a professional and durable result.

Please let me know if you have any questions.

Mitchell

[phiaxs]

Thanks for your in depth and complete answers Mitchell. Can I use Dulux weather shield for both exterior and interior trims? Is the finish very different with weather shield and Aquanamel? If I decide to stain and varnish my interior trims what products would you recommend? I understand there are dual purpose paints and products I can buy separately for staining and varnishing