Eli5 – what do they use to preserve railroad ties, utility poles etc vs stuff available to common mortals at big box stores?

Question

Most stuff in the stores says 1-2 years decks, 2-4 years vertical. Railroad ties, utility poles etc last decades… what do they use? Is it only available commercially?

In: 1

Answer 1

Having set and removed a many a creosote fence post in my youth, trust me, you do **NOT** want a creosote deck, lol