How to seal an outdoor decorative timber fence?

MatthewDarragh

Hi team, I'll be creating some outdoor outdoor timber fence panels consisting of 15mm marine ply painted monument as a backing board to DAR hardwood fence battens. I want maximum durability or the panels and battens. I'll be using a timber sealer. Do I use the sealer before the paint (marine ply) and stain ( hardwood battens), or after as a final coat?

MitchellMc

Welcome to the Bunnings Workshop community @MatthewDarragh. It's wonderful to have you join us, and many thanks for your question about creating a decorative timber fence.

When it comes to timber sealing and painting for your outdoor decorative fence panels, it's important to ensure that everything is properly sealed to maximise durability.

Firstly, we need to know what type of timber sealer you're planning to use. This is important because not all sealers are compatible with painted surfaces. Generally, timber sealers are used to protect the wood, but most are not designed to go under or over paint. In fact, any good quality exterior paint, such as Dulux Weathershield acts as a protective barrier that prevents moisture from penetrating the timber, so using a sealer might not be necessary after painting, depending on the type of finish you’re aiming for.

The key is ensuring that the paint fully seals the marine ply and that the oil and stain adequately cover the hardwood battens. You'll need to oil the battens as a stain typically doesn't offer enough protection; that's more for colouring. Think of the paint like a plastic wrap—it must completely encase the timber. If there are any gaps or fixings that penetrate the paint, water can easily seep through, potentially causing damage over time. That’s why applying a thorough coat of paint to the marine ply on all edges and sides before installation is essential and ensures that the coverage is seamless.

Once you’ve installed everything, it’s a great idea to go over any areas where nails or screws have been used to ensure there are no exposed sections of timber. This additional touch-up will help seal the fixings and prevent moisture from finding its way in.

Please let me know if you have any questions.

Mitchell