4

I have a nice deck, installed by a contractor years ago. We wanted to use the space under the deck as a covered patio area, so I built a drop-ceiling under the deck. It's made of overlapping panels of corrugated galvanized steel, supported by a cedar structure, with a slight slope so rain will drain off one end of the corrugated. I have four panel structures of cedar and corrugated, each three sheets of corrugated wide.

We were concerned that crud might fall through the deck and accumulated into a debris dam, and make the rain drip through where the panels overlap, rather than spilling off the lower end. My solution was to put a hinge along the edges of the panels nearest the house, so I can fold them down for occasional maintenance, then fold them back up to their normal, almost-horizontal position. So far, it works well, and the under-deck patio is a nice place to relax outside on a rainy Seattle day.

The problem is that I left unanswered the question of how to hold the panels in the almost-horizontal position when they're not folded down for maintenance. For now, I have some spare bar clamps grabbing the deck's main support joist, projecting out under the free edges of the panels. But I'll want to use those clamps again for something else, and they're not a good permanent solution anyway.

So, what kind of latch mechanism should I use to hold the panels in place? I've looked at various gate latches and tinkered with cardboard mock-ups, but no one answer jumps out as ideal.

Design goals include:

  • Secures the panels in position fairly securely, without loads that will stress the structures so they warp or bend over time, and loose enough so seasonal expansion and contraction doesn't gradually tear things to pieces.
  • Not a giant hassle to disconnect for periodic maintenance. It doesn't have to be as easy to use as a fence gate, but it shouldn't require tools, seize up if I don't unhook it for a couple of years, etc.
  • Doesn't require too many holes through the deck joists (pressure treated timber) or the cedar structure that will invite rot in this rainy climate.
  • Not unnecessarily ugly.
  • Not absurdly expensive or complicated to build and install.

Here's a cross section drawing. At left is the 10×4 pressure-treated deck joist that runs the length of the deck. The other brown rectangles are 5/4 cedar (which I mistakenly drew as 2×4s), the end-on edge piece at left, the cross supports at left. The bent gray line is the corrugated steel. (I gave up on trying to draw the corrugations.) The cedar hangs from a hinge at the right, out of the picture.

cross section

Here's an orthographic drawing. I drew everything except the cross section somewhat transparent, and drew the corrugated somewhat more transparent. The corrugated is attached to the tops of the cedar cross pieces with waxed stand-off pieces through the high parts of the corrugation with outdoor deck screws. The folded over part of the corrugated is attached to the edge with stainless steel screws (and zinc washers); all the inexpensive deck screws I could find were so long that they'd poke through the cedar.

orthographic drawing

Addition: Here's a photograph of the deck and under-deck ceiling. It shows pretty much the whole of the structure as described, including the bar clamps supporting the free edge of the panels.

photograph

Additional idea:

Based on the first reply, I had the idea of hanging some sort of hooks by chains from bolts through the deck's cross-joists, supporting catches attached to the cedar edge pieces. The first hooks could support the middle of each panel, hanging a little bit low, as the panels are raised to position. Then additional hooks at each end could support the panels at the design height and slope so they don't bounce around in the wind. Plastic-coated stainless steel cables might be better for the middle hooks, because they wouldn't rattle in the wind if they were slack.

  • 1
    A metal rod bent at a 90 to catch on the structure and hold the end in place would work if through the frame work, however I have not seen any kind of hinge brass , steel, aluminum that is in the weather and only used once or 2x per year that will still operate after a few years. – Ed Beal Feb 6 '18 at 8:32
  • 1
    Can you reach the joist/panel meeting location where the latches need to be? If no, do you want to be able to operate the mechanism(s) without a step-stool or ladder? – Jimmy Fix-it Feb 6 '18 at 15:14
  • @EdBeal: Useful point about moving parts sticking if moved too infrequently. That's something I'll have to try to design around. – Steve Feb 6 '18 at 23:15
  • @JimmyFix-it: I can reach the height of the latch without a step-stool, but my wife probably can't. But carrying a small step-stool down there isn't an excessive inconvenience anyway. – Steve Feb 6 '18 at 23:15
  • I had another idea about what to use as hooks for a chain: heavy spike nails, so that the nail heads keep the chain from slipping off the ends. Then the challenge becomes attaching the spike nails to the frame. My idea there was to use galvanized strapping for the main load, and small screw holes drilled through the spike nails to maintain alignment. – Steve Feb 13 '18 at 21:16
6

I would look at seeing if you could use large size slider bolts. I used this type of device to provide the safety latch for a large hinged stairway I had built in my garage some 13 years ago. The stairway was raised and lowered via an electric winch and cable/pulley system but I added two of the slide bolts (one on each side) as a safety measure when the stairway was in the hoisted up position. The ones that I used had round bolts that were 5/8" in diameter had a slide throw distance of about 3". They were plated with a typical hardware silver color.

You may want to consider something like these power coated sliders for your application outdoors.

enter image description here

In addition I want to suggest that you also consider a secondary safety mechanism to prevent injury and property damage in the case that the sliders are not kept latched fully. This could consist of some short chains that are lagged to the deck support beam and engage the hinged section via a hook on the side or end. These chains could hang loose when the slide bolts are in place.

  • 1
    The secondary safety mechanism idea of short chains gave me an idea: use chains as both the secondary and primary attachments. (That's worth the up-vote.) I'm not sure how to attach a slider like this one to my panels, and @Ed Beal makes a good point about an infrequently used latch out in the elements seizing up over time. I'll add more to the question. – Steve Feb 6 '18 at 23:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.