I recently moved into a 60-year-old house in the Bay Area that has a crawlspace, and I've noticed that the floor feels really bouncy. It even makes loud "boom" sounds when I step down with my heel, and I've seen furniture move when I walk nearby. The heaviest person in my home is 220 pounds, so I didn't think that should be a problem. Even my 3-year-old's running makes the walls vibrate! I found out that my house has a 'beam-only floor system', meaning there are no joists, which shocked me. I don't know much about construction, so I'm concerned if this is up to code. I plan to hire a structural engineer for a proper evaluation, but I'd love to hear from the community about options for fixing this issue before I proceed.
2 Answers
I've experienced similar bouncy floors, and it often comes down to the structure itself, especially in older homes where they use larger beams. Commonly, houses have a crawlspace with beams about 4 feet apart, and a 2x6 tongue-and-groove design for the flooring. If your hardwood is nailed directly to the subfloor, you might want to consider adding a layer of plywood under it for better stability. This setup will definitely cut down on the bounce!
It sounds like you're dealing with a pretty common issue. I suggest checking if your subfloor is really just resting on those beams. Sometimes, adding joists can help by sistering them to what's already there, plus putting in some mid-span joists and blocking could make a big difference. What I've learned is that this configuration allows for more rigidity. Without knowing the specifics of your setup, I'd recommend getting a structural engineer to evaluate spans and proper dimensions for reinforcements. Just be prepared for some hefty work!
That’s a good point! I think adding plywood could really help secure the floors before putting down anything else. It’s an extra step, but worth it for reducing that bounciness.