Probably not the job to cut your teeth on with a new "larger mig (farmer model)
I would get them made by someone who does it for a living.....
My .02, IMHO etc....

 

Is the finished wall going to be built out to accommodate insulation plumbing, or electric. As it is I don't think the 5 x 1/4 is going to give enough support, also you may want to use a tee shape tapered to support the steps. That could be made out of 5x1/4. The bottom leg of the t would be tapered and the top would be routed into the step. This should give a cleaner look with less mass.

 

What you going to do about a guard rail. It could add much support depending on how it is designed and attached. Good luck.

 

I have done some stick welding and a bit of mig welding, but you're likely right about getting the pros to do it. I'm stubborn though and will likely forge ahead with a bit of help.

 

No, the finished wall will be just the surface bonded cement, sort of a stucco finish. Wiring will be on the wall in conduit. I could go larger thickness of plate. I like the idea of the T with routering into the wood. Would likely look quite nice. I suppose the T would have to be 2 inch or more?

 

Good thought, the rail is likely to be metal ballisters with cable running lengthways for a bit of an industrial look. I guess the floating side could hang off of the cables.

 

Will your building structure that you are mounting to support the static load of the floating stairs? Do you have any idea of how heavy your stairs will be? Why type of live load are you designing for? Do you anticipate carrying anything heavy up these stairs? All questions you should have answers for before breaking out the farmer mig and beginner welder combination. Do you have local building permits/inspection requirements to satisfy? One other thing how does your liability insurer feel about your home built floating stairs?

 

I didn't calculate a live load yet. I would think that the stairs, estimated, would weigh? (300-400 lbs finished. I have building code to satisfy, as per rise/run and width, etc.

 

The idea sounds cool. What ever you do post photos of the finished product.

 

What type of safety factor have you designed for in your load calculations?

 

As far as wall support, it's hard to say without a lot more info on the wall. Length, height and so on also play a part in what it would carry. If I was designing a house and wanted to "float " the stairs, 8" of block wouldn't really be my 1st choice, even with bar and grouted solid. I've seen plenty of walls that were supposedly grouted" solid" that weren't because the masons were crap.

Personally I'd have wanted the wall thicker than 8", even if poured solid concrete. I know 8" of solid concrete would hold the anchors solid. but if the wall is long and unsupported, going up say 16'+ ( assuming 2 story) might cause issues with the wall cracking in the long run. Not so much from a structural issue but cosmetic if you are leaving the wall as is.

Block is very poor structurally in a side load configuration. That's why they would have grouted and used bar inside. However I don't know how they did that, what bar spacing, what quality of grout etc was used. Also 8" block doesn't leave a huge cavity to grout solid. Most "solid" walls I've seen grouted were all out of 12" block so you had a good size cavity to fill all the way down. Even then I've often seen where the masons were sloppy and filled a cell partially and you can't get grout or bar down those cells, so below that you have a hollow wall.

A lot of this would change if there's something on the back side of this wall to add stability, say a horizontal wall or floor.

As far as your steel, if I am visualizing this correctly, 4" tall heavy wall rect tube should support a step over that distance. 1/4" should be plenty to keep the tread from tipping on the tube. I'd rout the bottom of the wood to accept the plate at a minimum. If you are going with really heavy wood treads, you can probably hide a lot of the tube as well. I've seen some skeleton designs where instead of tube they build from pieces of plate that get cut into to heavy treads. That would require more design though though.


A bit of background on me. I studied Architecture in college and spent 15 years doing concrete for a living, both poured walls and decorative stuff ( stamped and stained concrete). I'd love to see what your stained floor ends up looking like.

 

The Wall is 8.5 feet high, dry-stacked 8 inch block wall with every third core rebar'ed. The cores were filled with a pumper truck and plasticizer to make it flow better, so I think there was pretty good filling of the cores. The outside is "surface-bonded" with quickcrete s.bonding cement which includes fiberglass. Strength of the wall is twice that of masoned block wall and even better than that side flexion/torsion due to the 1/8th inch minimum thickness bonding. The wall is also set into 7x11 inch supporting I beam on second floor, so I'm not too worried about side forces on the wall.

I could, however put rods with backing plates all the way through the wall to ensure hold. I will make sure to rout the bottom of the tread (have some thick 3" lumber) to get a good fit. I'll include one shot of the wall that also shows the floor a bit for interest sake.

 

I am far from an expert but here are a few thoughts. You say a load of 200 lbs but that doesn't allow for two movers carrying a 100 lb piece of furniture up. It also doesn't allow for two firemen carrying someone down on a stretcher (I saw this happen once with a heart attack victim, they could not get him down the spiral stair case and had to lower him down the side of the building from the window). Another though is your local building department, don't you have to submit drawings for your permit? If you do it is likely they will want an engineer's stamp on that stairway. If that ever came down all at once I would hate to be under it.

One of my clients has a stairway supported by a thick glass wall on one end, looks pretty cool. There is a hardwood structure in the middle of two back to back flights (acts as a hand-hold) with the glass on the outside ends. There are 2" chrome plated pieces of tubing with caps on them supporting the treads thru 2" holes in the glass. Believe it or not this is a two story master closet.

 

Yes, good point on the loads, then more likely each step, carrying up gyproc, etc could be supporting 300 lbs.

 

It sounds interesting though and of course we will need pictures or it didn't happen. What part of the world are you in?

 

I'm in Manitoba, Canada. Small town called Elkhorn, couple of miles out on 80 acres.

 

Ok, now you got me started. First the freshly (still wet) floor after staining.

And another angle after staining.

 

A bad drawing of the rough plan.

 

But ultimately, I trust the wall and the surface bonding and all the work hand pumping the cores. I really worry more if the weld will hold the load needed safely, and will there be any flex/vibration in the stair when using it.

 

Only problem with anchorage ......Just using expansion anchors won't work........ The best way would be anchoring thru stairs with threaded rods and backing plates on other side........ A 1/2" wall square tube about 4" min. would hold with a 1/2" mounting plate would suffice for holding a tread........ Remember to have all plans / details reviewed by an engineer ......( structural).

 

Ok, yes, I think the anchors through threaded rod with backing plate would be best too.

 

so guys, what about the 4 inch tubing. is the weld onto the 4 inch tubing strong enough on its own, or does anyone think that the angled bracing would be needed as well?

 

What about substituting a 2" x 6" x 1/4" tube for the 5" plate? Also use all thread through the block with a long flat plate instead of individual backing plates. That many wedge anchors guarantees that at least one will hit a week spot, not to mention with time they will pop the face right off the block.

Sent from my XT1045 using Tapatalk

 

I like your ideas, but think you should talk with a professional stair builder or architect in your area. I built stairs exclusively for 30 years, mostly wood, only did a few with metal and wood. Here's one with wood metal and glass I built. Retired now, but still go to the shop everyday and love it, my son runs it, he's be working with me for the last 20+ years.

 

Beautiful!

 

All this talk of floating stairs reminds me of The Staircase in Santa Fe http://www.lorettochapel.com/staircase.html

 

[video=youtube;NltT1YD-DxY]https://www.youtube.com/watch?v=NltT1YD-DxY[/video]

 

*video of stairs*

Very cool stairs. Your house is beautiful.

Thanks for the update.

 

i wasn't here back then but always nice to see a projects been completed.

i think the flaoting stairs are really gaining popularity. i had one set leave the shop last week and another in progress, be delivered tuesday

 

Nice clean look, I like it.

 

Nice! I have done a handful of stairways. They are my least favorite thing to build. Customers see all the pretty stairs in the architectural magazines and are unhappy when they can't have them because they are not code compliant.

 

Yes. I was originally going to go with a cable style of railing but it wouldn’t meet code. Also thought of glass rails but too expensive. The metal balusters were finicky but I think they look pretty good after all.