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Imagine a square room with four walls (12x12). Say you wanted to string a net across the area at a height of 6 ft, like a hammock. The net will be attached on all 4 walls, and it must support up to 400 lbs.

How would you go about affixing the net to the walls? Assume typical home construction - drywall over a wood frame.

Clearly you would have to first attach some kind of (metal?) hardware to the wall, which you would tie the netting to.

Any other ideas? Any recommendations on what product/material to attach to the walls? Any recommendations on netting material? Must be safe enough to hold up to 400 lbs worth of people.


Thanks for all the advice. Will upvote once I have enough rep. What if I did this?

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So basically run a 2x4 around the room. Then run the eye bolts through this 2x4, though the drywall, and into studs. That should help take some pressure off the walls right? And add some reinforcement to keep the walls from pulling inward.

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    Something to keep in mind is that the angle at which the hammock lies when under load dramatically changes the tension force which is applied by the hammock to the walls. Imagine for example you wanted no deflection whatsoever from a horizontal line when the hammock is loaded. Obviously the hammock would have to be infinitely tensioned for that to happen. Now imagine you suspended the hammock from the ceiling straight down, so the angle was purely vertical; clearly the tension with a 400 pound weight is 400 pounds of tension. – Eric Lippert Mar 13 '15 at 23:26
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    The true tension force you need to overcome is therefore somewhere between 400 pounds at a minimum, and infinity at a maximum, depending on the angle at which you want the hammock to make when loaded. What is that angle? a 400 pound load with an angle of five degrees supplies the equivalent of 5000 pounds of force to the wall, so it matters a lot. Do a web search for "sling angle factor" for charts showing the amount of extra force supplied as a factor of angle. – Eric Lippert Mar 13 '15 at 23:27
  • Thanks for the info. The netting will be attached at at least 10 places around the 4 walls so the tension should be distributed. – soleil Mar 13 '15 at 23:43
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As noted by others, you've got a startling amount of force applied to something that was never designed to hold that force.

If this was my house, I'd build a 4 sided frame of 1.5" square section steel pipe, set in the top corner of the wall and lag bolted securely in a few places per wall to the top plate. I'd also be sure that the corners were solidly bolted together. Use eye bolts to connect to the hammock. You could make most of it disappear by adding crown molding.

What this means is that you're relying on the steel to resist the inward pull of the hammock, and allowing the wall to carry a purely downward load.

If all that wasn't feasible, get an engineer to run the numbers.

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I would probably add a 1x4 (could cut and paint these to look nice) of maybe 12" to each of the spots I would connect the net. I would then buy some industrial size hooks - think of the hooks that you would typically get to hang your bike in the garage but nice. I would make sure that both wood and hook are attached/centered through wood framing.

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  • Thanks. Why the extra 1x4? Does that make it more stable than just installing the hooks straight through the drywall into the wood frame? – soleil Mar 13 '15 at 22:00
  • Maybe even a 2x4 if there will be a lot of weight - with just drywall it won't hold a hook, so it will not support anything. Meaning that section would sag and induce sag behind it. – DMoore Mar 13 '15 at 22:13
  • Ok. What would you use to affix the 1x4 to the wall? Nails? If so, what length? (assuming standard drywall thickness) – soleil Mar 13 '15 at 23:00
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I would use large wood threaded eye bolts, maybe 1/4" shaft diameter or more. These would go directly into the studs. I would then use carabiners as detachable connectors between the net/hammock and the bolts.

A word of caution though: Your walls are designed to hold weight pushing down. Your device will be pulling the wall sideways, and with a pretty significant force. Furthermore, if this is for people, that weight will be shifting around a lot. If your walls are 2x4 construction, you will likely see them deflect, which could damage the sheetrock. You should at the VERY least, connect to multiple studs so any weight is distributed across a wider area.

And maybe to test this all out, try hanging a single line across the room between two studs. Have someone pull down on it while you watch the wall for deflection.

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