A while back I alluded to this project. Finally time to stop the procrastination and get it underway. It’s a second staircase that was always planned as part of the house, but never detailed. Measurements were tight, so waited till walls were up to decide on final shape and direction. Finally bit the bullet on the engineering, and yesterday started the layout.
Here’s the design:
The leading edge of the first tread will be parallel to the pool table and about 5′ away. The staircase will curve till it meets the upper floor near that back wall.
Here’s where it will connect to the upper floor.
First step is putting paper down so I can transfer measurements to the floor and also protect the floor. Since my CAD file is nearby, I can easily get the coordinates for each corner of each tread. Rather than trying to find all the right angles using the back wall and a square or 3-4-5, the easiest way for me to measure is to have two fixed points, determine the proper tape length, and then stretch tthe tape to form the two legs of a triangle–it’s equivalent to drawing an arc the proper radius from each point and seeing where they intersect.
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Can't wait to see how it turns out. Will it be poured in place, or cast seperately? How do you shape the rebar for something like that? (don't know much about engineering, but interested)
Mrs. Guitarman
I'll show it all step-by-step as it progresses. It will be poured in place.
Wow! So cool, any idea when your going to have this completed? Looking forward to viewing your photos.
Edited 11/30/2002 12:57:41 PM ET by Armin a.k.a. The Laminator
ME speculate on a completion date?!?!?! Ha ha ha ha ha! (Actually, do have one in mind, but not foolish enough to say it publically.)
With your experience though, if you see improvements to make as this progresses, I'd love to hear them.
Railings will be steel tube to match upstairs balcony.
Codes people have any problem with that eight inch riser?
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Code I'm subject to allows 8 1/4".
Piffen, 8 1/4 applies to every place I build stairs, however one inspector did comment that 8 1/4 is the cut off point, build it 8 5/16 and out she comes.
I had heard 7-3/4" someplace. We don't go by codes here unless insurance presses it. I'm sensitive to it because I built one last year in a dead end hall space and it was 8-1/8" because that was the best I could get in this old house. The owner complained loudly, wanting more like 6-1/2" until I held his hand for an hour or two..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Piffin,
You hold hands! I prefer to wack em!
Figure of speech meaning, "tactfully take the time to explain to them how GD stupid their demands are so you can get paid and get more of that high dollar work"
Armin, take a look at the thread for cabinet software here somplace and see if you can help out..
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
, take a look at the thread for cabinet software here somplace and see if you can help out.
I found the site, sorry can't help, two things I know next to nothing about, women and software.
Soft women and hardware then?.
Excellence is its own reward!
"The first rule is to keep an untroubled spirit.
The second is to look things in the face and know them for what they are."
--Marcus Aurelius
Piffin, Now your talking, however hard cider and donuts is more my speed.
I think you're getting to the upper limits of comfortable risers at about 7 1/2. I prefer them closer to 7. Ask anyone with arthritic knees. Can't always do it, but it looks like there's space in your case there, Cloud.
Brinkmann for president in '04
I'm not complaining that I need more space! First plan was to run it along the wall toward the front door. But with a <7.5" riser, that were enough treads so that it came too close to the sidelight. So, while living here and getting used to where people walked, etc, came to like the idea of an S-curve. Thought it'd better balance the room than one hugging the wall. But if I make the rise smaller and add another tread, I come too close to the pool table. With the front steps being 8", I went with consistency. The spiral steps are ~9, so they're all a little higher than I'd normally do. However, in this case, any change seems to create a different awkward situation without its own easy solution.
hmmm, sounds like you're choosing form over function there, Cloud. Style over substance. If a home isn't people friendly, what good is it?
Brinkmann for president in '04
Choosing fitting over not fitting.
I build a lot of stairs for other people's houses, and I think 7 - 71/4" rises are the most comfortable, but that don't always fit. My own house, I've got 8" rises and arthritis...the rise is what works, the arthritis is what stops work! Just couldn't make the house wider, but still wanted to get to the 2nd floor...form definitley followed that function;-) and it keeps the old burglers out...
Funny, we've got an 8" rise max code, 'cept for top and bottom treads, in Chapel Hill, and today I put up a spiral stair with a 9" rise...I had to check that one out in the books...9 1/2" rise for circular stairs...!
Hey, anybody done a set of Salter spiral stairs? Want to help flatten my learning curve on the middle balusters? It's okay, I can fix it!
That 2y+x=26" formula is made to fit the human body. We tend to step closer when we step higher. My knees ain't that great, but I don't have trouble with steps steeper than 7-1/2", up to about 10", if they're laid out right. You've got 10" treads, so it should work just fine. Looks great!!
Formwork is 90% done. Had to chip into the slab a coupla inches under the front treads. Cleared out a keyway below the #6 bars so I can hook the rebar around them and keep the whole thing from sliding. Had to be especially careful be/c of the RFH. Was lucky to find the first PEX wrapped in insulation, so I didn't poke the tube. (It's near the manifold, so there's lots of tube there and some of it is insulated or we'd have a hot spot there.)
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The hardest part to form is the underside of the curved sections, because it's a twist. First coupla treads I could skip this on be/c they bond to the slab. That third tread was such an extreme twist that the hardboard wouldn't work. Had some 2" EPS scraps, and packed them in--easy to cut and sand the twist in those. Filled gaps with mortar.
The upper treads were tougher and it took me a day to get the 5 of them in. Their twist was about as extreme as the hardboard would take. I'll be adding strongbacks and other supports below, above, and anywhere else I can think of.
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Stringers were made from a pattern so that they'd fit right the first time. Used building paper trimmed to fit the curves, and then traced that onto the hardboard.
Had planned to finish the forming and pouring this week, but my pumper friend had to leave town, and I decided to wait for his return, rather than work with someone unfamiliar.
Holy smokes, nice form, cloud. You got a bunch of rebar running through there? What's that thing gonna weigh?
Edited 12/20/2002 10:12:22 AM ET by jim blodgett
Thanks, Jim. Net weight should be in the neighborhood of 5,000 lbs. Steel to be added soon. There's a bunch of it, of course. I'm cutting and bending the hairpins and other components outside right now. I'll show a detailed picture of it when done. The engineering is always fascinating to me. I can visualize, design, and build this stuff with a fair comfort level, but not the engineering, of course. Some of the most fun is talking with the engineer and coming up with solutions for the odd situations my designs create. He's a guy in his upper 60's and he has no hangup about talking me through the concepts and listening to my ideas and working things out collaboratively. Intensely creative process. In this case, we were fighting twisting torsion, and the solution for it will become a (hopefully cool-looking) design element that I haven't yet formed. That'll happen post-Christmas.
How much sag do you anticipate in the overalldesign? After the forms and temporary supports are gone shouldn't it droop until the compressed concrete and tensioned rerod find equlibrium?
Very impressive stairwork....
That's about as cool as it gets, great discription of the work. Are the tread surfaces concrete as well or are you going to do some sort of textured surface?
Was out of town, so couldn't get to a computer for a few days. Thanks, Stan. Armin, the treads will be glue-down bamboo--I'll be cutting 1" bamboo plywood to shape and bullnosing the edge. (some year) Will most likely finish the visible concrete with the same synth stucco as on the walls.
I really don't expect measurable sag--maybe an eighth or less. My engineer has been on the mark thus far. But since you asked, I'll make some measurements and let you know. Your guess is as good as mine. My real goal is that the formwork doesn't sag--that first 24 hrs after pouring I might sweat a little!
Finished the rebar yesterday. Double mat, with 4's and 5's, and hairpin hooks on the sides.
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Have spent several nights fretting over the formwork--what if this and what if that...it'd sure be one big mess.
Today was the big day, and it couldn't have gone better. Spent yesterday going back and forth on schedule and concrete mix. Ended up with 3000# pump mix with 3/8 structural lightweight aggregate. 112# per cu ft instead of 145 or so. Have to soak the aggregate for a day or so, or else it floats to the top, so got the order placed in a nick of time.
Spent last night adding more braces to the form and taping the edges of the form on the inside to try and keep water from leaking out. Spent this am adding even more bracing. Figured there was no harm in this, and a lot of harm if something went wrong. Just being a nervous nellie.
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Concrete company asked to have a field tech on site be/c it's a tricky mix to pump--we needed low slump so it wouldn't flow out of the forms, but too low and it won't pump. Finally settled on 3 1/2" slump, plus plasticizer, and it worked great. But damn, that mix sets up fast and we really had to keep moving. No water at all rose to the surface and not a drop leaked out. Only stopped up the pump once, and that magically seemed to resolve itself in about a minute.
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We had guessed that we'd have to pump in stages because of risk of squishing out the bottom treads as we added mud. So I did a driveway curb at the same time so we could alternate. Never needed to. We were all amazed how well it held. Even using a stinger (with very short "on" times) to make sure the rebar was encased, we had no problems at all with gravity, so we just kept pumping--first all the way to the top on the "stringer" and then working down filling in the treads.
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Most importantly, the forms held. Didn't even creak. And these guys were crawling all over them. No leaks, no blowouts, no cracked or bowed forms. The thing on the front of each riser is a section of PVC pipe I used to stiffen the riser form, by running tie-wire from the backside of the form through small holes in the riser and then around the pvc. The pvc made it easier to draw it tight, and meant I didn't need strongbacks. The system worked really well--as the weight of the concrete pushed down on the backside of the form, the tie-wire kept the riser form from bowing out.
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And lastly, a picture of the detailing at the top. Part of the weight is carried by the beam at the edge of the balcony. But a large part is being transferred to the dome wall. I turned these supports (real purpose is to counteract twisting tortion) into ledges that dw will use for plants or other decoration.
And in a coupla weeks I get to remove the forms and walk both on and underneath it. Can't wait!
Outstanding!
That is some interesting work. Good job.
Very slick trick with the PVC and the tie-wire.
This is one of those projects that will give you a smile for years to come.
Kudos! Turtleneck
Its not a smile- its a cramp
Beautiful work, as always. Those stairs are great. And to think, someone once posted that a house footing could never be cast to anything less than a half foot increment....that's not a mistake, it's rustic
Sweeeeeet lookin stairs.
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
Some large diameter coated (green) rebar for the railing system and you got a real conversation piece. That's a better looking job than the concrete subs did on my last steps and porch job and they only had to go straight up 4 risers.
Since I'm tying into pipe rail up at the balcony, I probably need to stick with that for consistency. But neat idea if I had done that everywhere from the start. Downside would have been on the spiral--my 5 yo rides down it on her armpit like Mary Poppins swooping into London. Think about rebar with that! Ouch.
How long will youb wait to strip? Isn't 7 days enough?
Why did you pour thge steps from the top down? I guess so you wouldn't walk in the fresh concrete. What kept the concrete from flowing down into the lower unfilled step?Do it right, or do it twice.
7 might be enough, but there's no rush. And since the stresses are pretty significant, might as well let the concrete get closer to spec strength. The test will be my impatience vs better cure. :)
We poured from bottom up, but only to the bottom of each riser. We thought it would flow down into and out of the bottom treads. And when we'd vibrate it to get it to fully encase the rebar, it would slide a little. If we had filled the treads on our way up, it woulda overflowed as we vibrated the treads above. Well, in about 15 minutes we found ourselves at the top step and everything was holding, so we worked our way back down filling, but not stinging, the treads. Used trowels to move excess mud down to the next tread so that we'd end up with nothing left over. Since we were inside, didn't want a mess to clean up. Still surprised it didn't flow more. Beyond the packed rebar helping, the biggest diff from normal was probably the mix--the lightweight structural was really stiff and sets up faster than normal, and besides helping with weight ('bout 5900# vs 8000#), it helped lessen downhill flow.
Most interesting project, well planned out, I never seen anything like it, nice work. http://www.northernsunwoodworks.com
Armin
Great site, didnt even notice who posted until I started to recognize some of the work.
Looks realy good!
Doug
Thanks Armin. Took the riser front apart--it had warped enough that it wasn't doing anything useful anyway--and am getting closer to a recognizable look...
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Awesome work....
You can be proud... A true example of construction as fine art.
I know this is a case of the tyro talking back to the master, but...
Took the riser front apart--it had warped enough that it wasn't doing anything useful anyway
Triggered a thought train in me widdow head... warped=wetter on one side...concrete expelling vapor=drying out...bad for strength. You probably know this already. Concrete cures because the moisture causes crystals to form interlocking matrices. Solution=after ALL excess water has evaporated (1-2 days) wrap the structure in plastic.
Please don't beat me, massah. :)
Man, would I like to work for/with you.
SamT
Such exaggeration! We're all just muddling through and filling our 24 hrs with something or other. I've been misting it regularly. It was actually just two of the 15 plywood pieces that had warped out about 1/4", so I figured I'd remove all of them (that damn impatience again) and patch any voids while the mud was still a bit wet (or not completely dry). That worked well. Probably shoulda covered it, but I've been misting it, and am leaving the bottom and side forms on for a coupla weeks.
Concrete is some of the coolest stuff ever invented. You did a real nice job of proving it!
You've told me once but I forgot - what design software are you using again?
Edit: Never mind, I took the time to find the thread again. I didn't realise that you could produce working drawings with Vectorworks. I thought it was just a rendering package. Nice design and execution Cloud.
Kevin Halliburton
"I believe that architecture is a pragmatic art. To become art it must be built on a foundation of necessity." - I.M. Pei -
Edited 5/8/2003 4:20:21 PM ET by wrecked angle
cloud... really nice... looks like some of the stuff ian did for the arabs...
the "s" adds a lot of elegance..Mike Smith Rhode Island : Design / Build / Repair / Restore
Thanks both of youse.
Ian's work in Saudi Arabia was my inspiration for this. I figured if HE could do it, then I sure as hell could. <G> Nah, I'm kidding. Ian's work showed me it was doable, and that started my quest to figure out how. I likely wouldn't have thought of it in this fashion if not for FHB and Breaktime. Can't wait to strip the forms next week! Eek.
Kevin, I think I used Deneba CAD for the simple drawings for this. Now it's all VW though--they put DCAD to shame.
jim.... it's amazing to me the things i've picked up here at BT.... it has certainly challenged me to keep pushing the envelope.... humble though when i see what some here have doneMike Smith Rhode Island : Design / Build / Repair / Restore
Stripping the forms took three partial days. Would been 2, but I had a helper (she's 5). Had a million screws to remove, plus some light touchup here and there (voids, screwheads, etc). Here's different angles. Not a single stress/shrinkage crack in the concrete yet, which really surprises me, so in revised answer to a question asked earlier in the thread, I expect there will be no measurable sag in the stairs...not even a 64th. Given the rather thin appearance, it feels rock solid. Now I can finish the bamboo floor before tackling the railing, etc.
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jim, fantastic !Mike Smith Rhode Island : Design / Build / Repair / Restore
Very graceful. Did I read you to say you're putting bamboo down for treads? Neat project. EliphIno!
CH
Thats a great looking set of steps! Have enjoyed the pics on this thread, keep em comin.
Doug
CH
Ditto Doug@es reply. Have really enjoyed the pics. Excellent job!
What type of handrail system are you going to use?
Davo
Bamboo for the treads. Will cut them from 4x8 bamboo plywood rather than using the T&G from the floor. Pipe rail to match the balcony. Still uncertain on finish. Was gonna use the blue-gray synthetic stucco on the wall behind, but now leaning towards creating contrast to highlight it. Maybe a white stucco...
That is neet . At the top were it turns toward the balcony you have concrete shoot to the wall , is that for support steel? or a design feature like a small offset landing ? I want to see a picture from the top looking down .
I want to see a picture from the top looking down
It's for both support steel and a small offset landing (DW's gonna put plants there that have trailing vines hanging way down). OK, the former's need was the mother of the latter's invention. That wasn't absolutely necessary, and it was engineered for just connecting to the beam, but when the engineer and I discussed it and he was educating me about twisting tortion, and I offered that the dome wall was just a few feet away, you could hear the sigh of relief. :) Even though this is an S-curve, there's actually a straight line from those landings to the bottom where it ties into the floor rebar and has a keyway. I imagine that at this point the beam is carrying very little weight.
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from underneath...
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And now for a bit of vertigo be/c of the way I shot this...
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number 2 cornfused me... just exactly what position did you have to contort into to take it?
Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
Edited 5/15/2003 9:27:14 AM ET by CAG
It's a wee bit Escher, huh? Just standing by the right side looking up from beneath.
Looking real good at any rate, can't wait to see the final pictures, good luckNever be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
Cloud: Your stairway project is most interesting to watch. You definately know what you are doing. Excellent posts.
Cloud,
Its fabulous. I see a lally column. Was it necessary to fill it with concrete, given the large concrete load on it?
Stef
The column was part of the original floor support--it supports the beam at the edge of the upper floor. Not concrete filled--just sized for the load. Most of the stairway weight is being carried by the dome wall now.
Cloud, I'm a full-scribe log kind of guy....but your work with these concrete domes is absolutely FANTASTIC! One of the very best things I have ever seen.
Did you think about putting radiant into the stairs?? I'm just joking...we both like radiant...and I assume you must have thought about it. Nice warm steps...all the way down!
Edited 5/16/2003 4:00:19 PM ET by PIRGERBRUCE
There you go ! that last picture is the one that I like to see . It is kool to look down curved stairs . I like that landing /display / support detail.
Cloud,
Looking very cool, are you going to leave the pipe natural or painted, I wasn't sure if that is what you were talking about finish?
If you decide to paint, look into powder coating instead of paintingNever be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
For color, was talking about the concrete. For the railings, a dark paint. Doesn't powder coat get baked? Am I thinking the right thing? These railings will be built and welded in place.
yeah powder coating has to be done in a shop, it is electro-statically sprayed on then baked
It is much more durable then paint, will give you nice even finish, looks better then paint, but that's just my opinion, most are more chemical and scratch resistant then paint. and should never need regular matinence like paint.
If you could weld up the rails before you installed them, a powder coat shop should be able to do them, I went to watch the process once, and the "oven" was basically the size of a one car garage.Never be afraid to try something new. Remember, amateurs built the ark, Professional build the Titanic.
>If you could weld up the rails before you installed them
The posts will screw over bolts that are already in the concrete, plus, gotta weld it to the railing at the balcony, which itself weighs about 600 lb. Still, good idea for another time and place.