We spend our summers restoring decks and porches and our winters plowing and salting, so we see both sides of the problem: you need your steps safe, and the things that make them safe are hard on wood.
Rock salt — sodium chloride — draws moisture into wood, dries out the fibres as it evaporates, and leaves a residue that breaks down sealer and stain. It also corrodes the fasteners and metal brackets holding the structure together. Over a few winters, salted stairs and landings are usually the first parts of a porch to grey, split and loosen.
Start before the snow. A deck or porch that was cleaned and sealed in the last year or two sheds water and salt far better than bare wood. If water soaks straight in when you sprinkle some on the boards, try to get it sealed before the first freeze.
Use the gentlest melt that does the job. Calcium magnesium acetate and many pet-safe blends are much easier on wood and metal than rock salt. Use as little as you need, and sweep away what's left once the ice is gone instead of letting it sit.
Shovel carefully. Metal-edged shovels gouge softened wood and chip stain. A plastic shovel, pushed along the boards rather than across them, does far less damage. Leaving a thin layer of snow is better for the wood than scraping down to the boards.
Clear your gutters in the fall. Overflowing gutters dump water onto porches and stairs, where it freezes into ice that needs even more salt. Clean gutters and working downspouts keep that water away from the wood.
In spring, wash it off. A gentle cleaning removes the salt residue, grime and any mildew that grew under the snow, and shows you whether the sealer survived the winter. If it didn't, that's the time to re-coat — before summer sun finishes the job the salt started.
We do both halves of this: snow removal with pet-safe melt available in winter, and deck and porch restoration in spring. Call (312) 869-4688 for a free estimate on either.