Hi my boyfriend bought a bench and chairs of untreated wood and does not want to stain or paint it thinking it will just 'age' nicely. Sadly he won't listen to the fact that it will warp, mold and possibly become infected with insects if untreated. This message can't come from me though he WILL however listen to experts so could anyone kindly rely to what happens if you leave fully u treated wood outside (as outdoor furniture) thank you!
What's "age nicely"? Yuck gray, cracked, checked, full of splinters and dry rotting apart in 10-years? Yay?...even if it's an exterior grade wood. Why buy something if you plan on neglecting it and then blaming it for being a piece of garbage?
If they're in the Sun. Just easily and quickly slather it up with One-Time Wood Protector every 7-years. It's the only stuff I use anymore and only the first year of their Natural/Clear has any noticeably darker color. You buy it once and use it until empty, it's got an indefinite shelf-life.