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Thomas Marr
12-08-2011, 9:24 AM
When I built my shop, I had the contractor "stick build" the roof so I could use the upstairs as storage. It tuned out much better than I expected and I'm spending more and more time up there. However, in order to save space, I installed fold down "attic stairs" rather than a permanent staircase. That was a mistake. Since I'm using the area more than expected, I've decided to improve access.

A gentleman posted the video below on YouTube showing a retractable staircase. The is exactly what I need. I send an email asking for details. Anyone built such a thing or have comments about how to build it?

http://www.youtube.com/watch?v=8QlEnVhoq4M&feature=channel_video_title

Thomas Bank
12-08-2011, 10:43 AM
Looks like pretty straightforward construction for the stair itself (stringers, treads, and such) and then just hinged at the top. The trick is getting the springs set up with just the right amount of tension to retract it fully without slamming it up into place.

Anthony Whitesell
12-08-2011, 10:47 AM
I don't think the one in the video is using springs. It appears to me to use gas shocks, the same type of thing that is used to hold up the back door on a minivan or SUV.

Andrew Joiner
12-08-2011, 11:29 AM
What if a gas shock fails (and they do)? It could be deadly if someones is under it.

I designed my stairs similar to the video, hinged on top ready to lift. I planned to use my Harbor Freight hoist. I used it to lift up the 2nd story floor sheathing and it worked fine. As I used it I never stood under the weight being lifted and thought " how can I avoid ever passing under the lifted stairway?"

Bottom line is it would never be fail safe without a complicated latch and handrail.

The stairs are in and they aren't in the way as much as I thought. It's more convenient to leave the stairs AND handrail in place. I run up there once or twice a day. The handrail is nice for carrying big stuff. I can touch it with my hip and lean that way rather than fall off. A handrail complicates a lifting design.

I did make the handrail removable so I can manually lift the stairs 3.5'' off the floor and set it on 4x4 blocking. I need to do this to rip wide stock over 8' long.

Kent A Bathurst
12-08-2011, 11:47 AM
I doubt there is much risk of an instant, total failure of both of the struts at the same instant. They would tend to lose pressure, and "sag", not crash down - kind of an early warning system.

However - I "helped" a neighbor build and install a 30" x 60" trap door in their deck, leading down to the basement [the only access is from outside where the flap-open cellar door used to be]. The PT lumber has dried over the past year, so the door is much lighter than when installed. The struts would now probably hold it up in the open position, but we attached a chain that loops around to an eye screw on a window sill, as a safety mechanism for his wife's peace of mind - didn't want someone trapped.

Jim Finn
12-08-2011, 11:50 AM
I once built a stairway similar to the one in the video but I had it to store vertically against the wall and just pulled it out to use. I had rollers ,top and botton, and a stop at the top to keep it in place while using.

Thomas Marr
12-08-2011, 12:37 PM
He is using Gas Springs. The challenge is to calculate the proper force. You can buy them inexpensively from McMaster with a force all the way up to 550 lbs per spring. Since they are hydraulically dampened, you don't have to be perfect in the calculation. However, if you aren't "close," they'll be a pain to pull down. I did find a link to a formula for calculating the force. Here's the link: http://www.practicalmachinist.com/vb/general/help-sizing-gas-springs-retracting-staircase-232796/
(http://www.practicalmachinist.com/vb/general/help-sizing-gas-springs-retracting-staircase-232796/)

Dave Wagner
12-08-2011, 12:43 PM
You could use some old cast iron window weights and pullies?
I put a pull down stairway from home depot for my access, works good, since I don't go up there a lot.

Mike Henderson
12-08-2011, 3:41 PM
You can buy commercial versions of that stairs. I bought one at Home Depot and installed it myself. Mine folds in the center so it doesn't take that much room out of the upstairs floor. On mine, you pull it down the way he did in the video, and the stairs is folded on itself. You fold out the stairs and use it.

But I'm sure people know of these stairs. If not, I'll take pictures.

Mike

Thomas Marr
12-08-2011, 4:29 PM
Mike, are you talking about typical attic stairs? I already have a set of those. However, there are several problems:

+ They're not made for every day use. Some of the brads in the steps are already loose (hey, I'm a big guy).
+ The angle is WAY too step to come down the stairs in a "normal" fashion. So, I have to back down like you would using a ladder.
+ The steps are too narrow. So, I must use the hand rail to go up and down (too hard to carry anything).
+ They require multiple steps to "unfold" (at least mine does).
+ They're a pain to fold up. My ceiling is high enough that I can barely fold them up without a step stool. My wife can't fold them at all due to the weight and height.

David Gutierrez
12-08-2011, 5:17 PM
i second the counter weight idea. So simple it is not prone to failure, less expensive and you can add / subtract weights until you get it just right.

Bruce Wrenn
12-08-2011, 8:10 PM
i second the counter weight idea. So simple it is not prone to failure, less expensive and you can add / subtract weights until you get it just right.For counter weight, use a bucket filled with sand,or gravel. Be sure to loop rope under bucket, not just attached to handle.

Bob Faris
12-09-2011, 2:46 AM
Have you seen the Bessler disappearing staircases?

http://www.bessler.com/

Thomas Marr
12-09-2011, 9:09 AM
I'm fine to try the counter weight idea. However, where can I connect the cable to the stairs? For example, if I connect the cable in the middle of the stairs, it will be in the way. If I connect to one side, won't this have a tendency to "twist" or torque the stairs. Also, how does one optimize the weight? With gas springs, you can design the system so that leverage is reduced when the stairs are extended. Therefore, the stairs will stay in the down position or up position (like shown in the video). With weights, it seems like it would be hard to achieve equilibrium in both positions.

Kent A Bathurst
12-09-2011, 9:22 AM
IMO - the struts are the ticket. You can get ones that are adjustable, which would [should] allow you to dial them in.

Thomas Marr
12-09-2011, 9:57 AM
Have you seen the Bessler disappearing staircases?


Those are very cool.

Andrew Joiner
12-09-2011, 11:31 AM
Thomas, The bessler is a cool design, but the biggest weighs less than 190 lbs and at 19'' wide it's more ladder than stairs.

Do you need a door/hatch to seal heat/cooling from your second floor? I have one so it complicates a Bessler type design. My stairs end 5' from a wall on the 2nd floor and at 17' long they weigh over 400lbs. so the Bessler style is out for me.

Sam Layton
12-09-2011, 11:51 AM
Thomas,

I have the Bessler disappearing staircase in my house. Easy to pull down, rated at 800 lbs, it is a pull down staircase, not a pull down ladder.

Sam

David Thompson 27577
12-10-2011, 1:36 PM
When I built my shop, I had the contractor "stick build" the roof so I could use the upstairs as storage. It tuned out much better than I expected and I'm spending more and more time up there. However, in order to save space, I installed fold down "attic stairs" rather than a permanent staircase. That was a mistake. Since I'm using the area more than expected, I've decided to improve access.

A gentleman posted the video below on YouTube showing a retractable staircase. The is exactly what I need. I send an email asking for details. Anyone built such a thing or have comments about how to build it?

http://www.youtube.com/watch?v=8QlEnVhoq4M&feature=channel_video_title


I've seen (videos of) stairs done with gas shocks, and with cable/spring coils.

In addition, my 1949 house has a truly retractable attic stair. The access door is 54" long, and the staircase reaches the 8-1/2 foot ceiling.

When I pull down the access door, the (fully solid, not hinged or collapsable) stairway slides down on tracks. When I'm done, I first push the stairs back up into the attic, then lift them and the access door to the closed position. All is done with cable/spring coils, so no heavy lifting is involved. Note that this requires attic space to store the retracted stair.

Joseph Klosek
12-11-2011, 9:08 PM
I built a retractable stair for a customer this year that uses a set of antique blocks with a sailboat winch. The stair was 36" wide with 13 risers at 7.25" and a 9" run. This made the stairs about 13' long so the last 3' feet fold under in order to fit in the well hole.

The stringers have open treads with no risers so I made the stringers from 12' x 2' LVL and veneered them with 1 piece of 1/4" baltic birch ply on both sides with 1/16" cherry veneer. The treads were solid cherry. The whole thing weighs around 350 lbs.

The block and tackle system work well, but it was originally planned to have a winch. However time constraints made the manual system more simple to install.

I used a heavy piano hinge for the top and made my own hardware for the folding bottom treads.

If you want I could post some photos and get the info on the hardware.

The issue I see with the u-tube design is that the hardware and support system all hang below the ceiling plane. I was not able to have that with my design, so everything goes up into the ceiling and nothing is below the ceiling plane.

J.P.