After much searching, I can't find anything about whether it is best practice to paint over screw heads outdoors or not.
I am in the process of building a couple of outdoor benches and a table from non-impregnated wood, which I then plan to paint with window paint. For the first bench, I have oiled the end grain and joints, and have primed and applied one coat of top paint before assembly. Initially, my thought was also to apply the final coat before assembly, but then I started wondering about the screws. Is there an increased risk of moisture seeping into the wood where the screws are, especially if cracks form in the wood? Would it then perhaps be best to apply the final coat after assembly, and then also paint over the screw heads to reduce that risk?
Some screws will be hidden and horizontal, but a number will be vertical, with the screw heads facing upwards towards sun, rain, and harsh weather.
I am in the process of building a couple of outdoor benches and a table from non-impregnated wood, which I then plan to paint with window paint. For the first bench, I have oiled the end grain and joints, and have primed and applied one coat of top paint before assembly. Initially, my thought was also to apply the final coat before assembly, but then I started wondering about the screws. Is there an increased risk of moisture seeping into the wood where the screws are, especially if cracks form in the wood? Would it then perhaps be best to apply the final coat after assembly, and then also paint over the screw heads to reduce that risk?
Some screws will be hidden and horizontal, but a number will be vertical, with the screw heads facing upwards towards sun, rain, and harsh weather.
When it comes to outdoor paneling, screws/nails are painted over. In your case with outdoor furniture, I would use corresponding hot-dip galvanized screws class C4 or stainless steel screws, especially if it is pressure-treated wood. Now you have regular wood, so C4 should work well. You don't need to paint over the screws.
Example
https://www.heco.se/sortiment/trainfastningar/traskruv-protect-4.html
Example
https://www.heco.se/sortiment/trainfastningar/traskruv-protect-4.html
Great tips regarding screw choice! With the question, though, I am not really considering the screw's lifespan (I have C4 screws for the purpose), but for the wood closest to the screw. The risk of moisture penetration and subsequent problems should decrease with a final coat when the screws are in place, right?ClasseClas said:
Either paint over or rather pre-drill and countersink for the screws. Make sure to prime and paint in the holes before assembly. Usually (I think) you want to be able to disassemble and renovate outdoor furniture, and then painted-over screws are not fun.