r/Carpentry • u/Visible-Equipment928 • 13h ago
Framing Structural question: 6×8" joists, 16.4 ft span, 39" OC with living space above
I'm looking for some structural advice.
We have an old farmhouse with a timber floor system. The living room is spanned by 6×8 inch (15×20 cm) wooden joists over a 16.4 ft (5 m) span, spaced 39 inches (100 cm) on center.
Above it is a lightweight attic conversion with drywall partition walls, two small bedrooms, and a bathroom. One of the bedrooms is directly above the living room.
Does this sound like a reasonable structure, or would you recommend having a structural engineer inspect it and possibly reinforce the joists? There are no obvious signs of failure, but I'd like to know whether this framing is typically considered adequate for this kind of load.
Thanks!