I plan to build some steps into a sloped hill, using timbers. I had some built about ten years ago, and used PT lumber rated for ground contact, which was .8 penetration level.
I know that the chemicals used, and applicable ratings, have now changed for PT lumber. What would the equivalent now be for what was .8 "ground contact" ??
I also previously used 12 inch galvanized sprial nails to connect the timbers to make the steps. Will these nails be ok for the new type treated lumber ? I buy them at Home Depot, and they are not labeled hot dipped or anything like that. They just say, galvanized nails.
I "think" that I will use 6 x 6 PT beams, like I did before. But, some articles refer to "landscape timbers." Exactly what are they referring to ? I don't want to use railroad ties... I want a more updated look, which the 6 X 6 beams provide. But, there may be a more suitable and long lasting type timber that I should use, and I would like to know more about my options.
Thanks for any advice on these many questions !!