Here is a rendering of a staircase we need to build this summer. It is against an outside wall with curved returns, thus the curvature seen in the landings. Landing framing is 2×6, but we are thinking of making the curved “ledger” parts of the frames using wacky wood, three plies of 1/2″ x 5-1/2″, glued and screwed. Stud spacing at the curved sections will be 6″ or so, so there is plenty of opportunity for nailing the ledgers. The inside straight sides of the landings, as well as the inside stair stringer, will bear on a studwall, part of which can be seen (there is a door going under that leads to a cellar stairs.)
Any other suggestions for fabrication of the curved landing framing?
Replies
Sorry, I didn't have the preferences set to "advanced view," thus could not post the pic. Here it is.
Micro given that the the radiused sections of the landing are against bearing walls and not really "holding up" the staircase per se wacky wood bent like you are describing should be okay. The only thing the curved "rim joist" that you are fabricating is really holding up is the sub floor and flooring of those particular landings.
We wouldn't use wacky wood laminated or otherwise for any long spans of an unsupported curved stairway though so I recognize your question as a good one to be asking. There are better stronger ways to make curved stringers and there are some other problems you would discover if you used wacky wood for extended stringers. I know,...been there, done that.
View Image
"Function is based
on more than utilitarian factors. Ambiance invites use."- Sarah Susanka
Thanks for the feedback. The job we trimmed out last winter had a quarter-circle barrel-vault ceiling, and we used wacky wood up against the curved ceiling joists as a substrate for the finished bevel-edge cedar strips. Did some window trim and stair features laminating 1/8" maple strips against forms to build up to 7/8" finished curved trim boards. We thought the wacky wood would be easy to work with this time, and when built up to a cleat of 1-1/2" should work fine. Our other option might have been to bandsaw shorter cleat sections from large cants of pine or fir.
" Our other option might have been to bandsaw shorter cleat sections from large cants of pine or fir." ---Whoa, way too much work for what it needs to do and as Joe Carola is saying you can really even do it without bending a ledger at all.
The only reason I wouldn't do it Joe's way is we are a real stair shop amongst other things and we might build that whole friggin assembly in our shop and finish it off there too before breaking it down and going off to install it. That would require us to make the landing components rather than framing them in place at the project venue. I just hate building stuff in place.
View Image
"Function is based
on more than utilitarian factors. Ambiance invites use."- Sarah Susanka
Micro,
You can frame it without a bending a ledger if you want.
Nail the 2x6's along side the wall studs on the square section at 16"/oc and then nail the 2x6's every other 2x4 on the round wall if there 6"/oc.
Joe Carola