Hi I’m looking to paint an a mural on a north facing wall on panels that would be screwed into the wall. What would be your best product to use that will be weather resistant and stand the test of time!?
I plan to prime, thinking Zinsser and then use acrylic exterior bright paint and finishing off with a clear top coat!?
Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thank you for sharing your question about what material to use for an outdoor school mural.
If you wish to use timber, I suggest using 2440 x 1220mm 12mm Plywood Hardwood Marine AA Grade. It is constructed for outside use. But if painted over, will last a long time. Next is James Hardie 2400 x 1200 x 4.5mm 2.88m² HardieFlex™ Cladding. This material is used for external house cladding and will provide a long service life. Your third option is to create a picture frame panel out of Merbau and render the inside in cement to give you a flat painting surface.
Each material has its weaknesses and strengths. The plywood being made of a natural material will be subject to temperature movement. The HardieFlex Cladding does not respond well to inadequate mounting support. The cement render if not done properly could possibly crack. Their common strength is that they are all built for outside use. I suggest visiting your local store to see these materials I've mentioned.
If you need further assistance, please let us know.
Thanks so much Eric, really appreciate your time and advice. Went in on my way home from work and looked at all the options. At this stage the Marine Ply look like the go as I have used the James Hardie cladding for a previous project and it did crack on the edges upon installment.