Hi! I am considering using either plywood or 1x6 pine boards as an inexpensive alternative to hard floors. But as I read about it, I have a few questions that I haven't been able to find answers to. I just found this website in my search and I'm really excited to pick the brains of experts! Anyway, here are my questions:
Not wood, but related to the project: I need a barrier between the subfloor and planks. I've seen where people have used exterior primer/paint for the barrier. Others have used roofing/tar paper under the flooring. Which would be better? If I were to use roofing/tar paper, is it safe for interior use?
About the wood: If I use plywood, I've read that you're supposed to leave a gap between the boards to allow for expansion. But I've seen where people using pine boards don't leave a gap. They say that pine boards shrink over time. Is that true? Should I leave a gap or not? And wouldn't plywood shrink over time as well?
Do pine boards get harder with age? Does plywood get harder with age?
When protecting the boards, I've seen where some stain/poly the planks individually before installing them; others install the planks first, then stain/poly the whole floor at one time? Which would be better for a longer-lasting floor? I'm thinking about the expanding/contracting of wood and whether or not it would affect the finish.
And lastly, should I nail the boards down or use screws? I'm hoping this alternative flooring will be durable enough to last at least 10 years.
Any information you can share will be much appreciated. Thank you!