Just read that a 3/4 inch solid hardwood floor can move up to a full inch across a 20 foot span

Found this in an old trade manual from the 90s I picked up at a garage sale. It was talking about seasonal humidity changes. I always knew it moved, but a whole inch? That explains why some of those old nail-down jobs I've seen have such huge gaps in winter. How do you guys even plan for that much movement on a big install?

3 comments

3 Comments

emmaj3318d ago

Wow, that's a crazy amount of movement! It makes you wonder about all those giant open-plan floors in modern houses. If you run the same flooring straight through from the living room into a sunroom with big windows, the humidity change in that one room could be way different. You might get a serious buckle or a huge gap right at the doorway where the two areas meet, even if the install was perfect. Do they have to treat it like two separate floors?

patricia31718d ago

My uncle's sunroom floor buckled a full inch last summer. So @emmaj33, your point about different humidity in one room is dead on. Wouldn't the whole floor still try to move as one piece, like bennett.riley said, but then fight itself? That stress has to go somewhere. I guess the installers have to plan for the worst case humidity in the whole connected space, not just the average.

bennett.riley18d ago

You're right about the movement, but that "huge gap right at the doorway" idea is a bit off. The whole floor moves as one big sheet, it doesn't just stop at a door. The real trick is leaving the right size gap at EVERY wall. In a big open plan, you need a continuous gap all around the edge that gets covered by the baseboard.