Q: How should I prepare dirty, interior wood stairs for finishing? I’m remodeling my parents’ home and part of the work involves finishing a staircase that was left bare and unprotected after it was built 10 years ago.
A: Dirty wood looks ugly, but you’ll be encouraged by how beautifully it cleans up. The only option for removing ground-in dirt like you’ve got is sanding, but you must start by vacuuming. Remove all the loose dirt, then wash the stairs with hot water and a little dish soap added. Let the stairs dry for a couple of days without using them, then sand. Open areas could be done with a 5″ random orbit sander using a 180-grit disk. For corners and hard-to-reach places you’ll need a power tool called a detail sander. It has a small, triangular sanding pad that allows you to get into nooks and crannies.
As for what to finish the stairs with, urethane over stain looks nice at first, but it’ll get scratched and worn out. And the problem is, you can’t repair a urethane-and-stain finish easily either, unless the scratches are very small. This is why a better option for stairs is urethane only. Coloured finishing oil also works well if you want to add colour plus protection. That’s what you see here. I built these stairs 3 years ago, finished them with coloured Danish oil, and they look fabulous today, even after lots of use. When it comes time to freshen them up, a good vacuuming and another coat of oil will do the job. Although finishing oil doesn’t shine like urethane, it’s beautiful and repairable. When the finish looks tired, just add another coat and things are as good as new.
Got stained-and-urethaned floors or stairs that are looking pretty ratty? Watch the video up next to see a DIY option for making them look great again without sanding all the way back to bare wood.