How to protect new exterior stairs?

Mech

Hi,

I am looking to protect a newly built exterior stairs. The stairs goes from carport to a merbau deck. Mostly pine with a merbau hand rail. I was thinking of painting the stringer and posts and staining the threads to be a similar colour to the deck boards. Do I need to seal between stringer and threads? Any recommendations for anti slip protection.

Thanks,

Donal

u deck.

JacobZ

Hi Donal (@Mech),

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

That sounds like a great project and a good way to tie everything in with the deck.

For the stringers and posts, painting is a solid option. Make sure the timber is dry and if necessary, lightly sanded, then use a quality primer that is suitable for exterior use such as Dulux 4L 1Step Prep Primer, Sealer & Undercoat, followed by two coats of an exterior paint such as Dulux Weathershield. A low sheen or satin finish tends to perform well outside and is easier to maintain than full gloss.

For the treads, I would recommend using a penetrating exterior decking oil or stain rather than a film forming varnish. A merbau tinted decking oil such as Cabot's Merbau Water Based Deck And Exterior Timber Stain will help blend the pine treads closer to the deck boards while still allowing the timber to breathe. Start by scrubbing the timber with a deck scrub brush and Cabot's Deck Clean, then apply two thin coats of oil and plan for periodic maintenance coats depending on exposure.

In terms of sealing between the stringers and treads, you generally do not want to fully seal that joint with silicone or a flexible sealant. Stairs need to be able to drain and dry out. If you seal that junction, you can trap moisture and potentially accelerate rot. Instead, focus on coating all faces and especially end grain before installation where possible. Making sure the timber is well sealed on all sides is more important than sealing the joint itself.

So, if you can remove the treads, oil them on all sides, and paint the pocket in the stringer, then allow everything to dry before reinstalling the treads, this would provide you with the best protection long term.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob