Rooftop cable for clipping-in safety harness

[olytdi]

Tell me you think this is viable:

I have a 28x28 pole barn with a shallow pitch roof (4/14) under a bunch of very large and very productive trees. I have an on-going problem with accessing it safely to get branches and leaves off. It's corregated steel and slipperier than snot even when dry. On the front side of the building, it's a 12 ft drop if I fall. On the back, it's about a 16 ft drop. I don't want to fall and access to the roof by ladder is not only difficult due to a slope in the back, but I cannot reach very far up the roof from the ladder.

I've pondered and pondered how I might be able to get up there and clean-off the 4 inches of detritus that builds up over a year and came-up with this idea: there is a 10"x12" main post on each end of the building from floor to peak. These are just inside of the siding and support the two end trusses. My thoughts are to take say, 2.5" galvanized pipe and strap a 3 or 4 ft piece vertically along the outside of each end of the building along these posts such that the pipe extends up through the eve and above the peak. So, there would be a roof peak with a piece of pipe extending up above by a foot or so on each end of the building. I feel that I could cut through the roof to do this because that part of the roof on each end is outside of the building has an 18" overhanging eve. So any leaks presumably would occur outside of the building not inside.

Perminently fastened between these pipes would be a length of wire rope that would reside about a foot above the peak strung from end to end. I would then use this secured cable to clip into with my harness and be able to walk around without fear of falling. Because the attachment cable would be free end-to-end along the peak, I would have unfettered ability to move from end to end of the roof.

Does this make any sense? What am I missing --it can't be this easy can it?

Thoughts, critique, tips?

thanks!

 

[mrb]

you need it engineered. pulling sideways on a cable between two endpoints with a couple hundred pounds can put an exponentally larger amount of force on those endpoints.

 

[Doctor_Ink]

Dont forget about hornets that love to nest under those over hangs, and would love even more to crawl into those gaps...

 

[olytdi]

Good point! Seal the pipe ends.

 

[Gary S]

Is the building situated where you can park a pickup on both sides of the building? If so, simply park on one side, tie a rope to the truck, and toss it over the peak. Then when you are up there, tie the rope around your waist and work until finished. Then move the truck to the other side and repeat.
When I was a kid, I helped my Dad dismantle a 3 story house with a very steep roof. We started on the roof using this method, removed shingles first, then roof boards, and worked down. Nobody fell of the 35 foot high roof.

 

[akdiesel]

Is the building situated where you can park a pickup on both sides of the building? If so, simply park on one side, tie a rope to the truck, and toss it over the peak. Then when you are up there, tie the rope around your waist and work until finished. Then move the truck to the other side and repeat.
When I was a kid, I helped my Dad dismantle a 3 story house with a very steep roof. We started on the roof using this method, removed shingles first, then roof boards, and worked down. Nobody fell of the 35 foot high roof.

Just don't forget to put every key to that vehicle in your pocket or you will have one hell of a ride.
I use this approach sometimes as well. Just keep in mind when close to the peak edge since it could slide over if you fall.
There is also an older product that attaches to the roof sheeting where the truss support is. It is attached by screws and goes under the shingles. It has an eye for carabiner attachment.
http://www.bestmaterials.com/Roof_Anchor.aspx
Usually a 60 deg angle is the max for rope. Not sure what it is for cable. There are systems in place that utilize a straight cable lanyard for fall protection.

 

[fury9]

what if you get a rake/pushbroom or whatever will work best and attach a 10ft handle to it to pull or push the leaves/branches off? Maybe put some grip tape stuff going up to the ridge so you can get up there then just push the junk off while working from the ridge? OR what about some magnetic shoes haha

 

[olytdi]

you need it engineered. pulling sideways on a cable between two endpoints with a couple hundred pounds can put an exponentally larger amount of force on those endpoints.

I may inquire about those loads. My plan would be to really over fasten it to the 10x12 like in four places with clamps and lags. Thanks for chiming-in!

 

[Lotek]

I would just use a padeye at either end with a stainless cable in between, it can lie flat on the roof and you won't have any problem sliding your safety line from end to end.
You may want to consider using nylon webbing and taking it down when you aren't using it, how safe will that cable be in 10 years? That's how it's done on sailboats, and for exactly the same reason. Look up jacklines

 

[olytdi]

Is the building situated where you can park a pickup on both sides of the building? If so, simply park on one side, tie a rope to the truck, and toss it over the peak. Then when you are up there, tie the rope around your waist and work until finished. Then move the truck to the other side and repeat.
When I was a kid, I helped my Dad dismantle a 3 story house with a very steep roof. We started on the roof using this method, removed shingles first, then roof boards, and worked down. Nobody fell of the 35 foot high roof.

No and that's the problem. I do that very thing when on the roof of the house -- tie-off to my Trooper. Won't work on the shop.

 

[olytdi]

There is also an older product that attaches to the roof sheeting where the truss support is. It is attached by screws and goes under the shingles. It has an eye for carabiner attachment.
http://www.bestmaterials.com/Roof_Anchor.aspx
Usually a 60 deg angle is the max for rope. Not sure what it is for cable. There are systems in place that utilize a straight cable lanyard for fall protection.

Thanks -- unfortunately, there are no shingles or roof sheeting. Just trusses, 2x8s and painted metal sheeting.

 

[olytdi]

what if you get a rake/pushbroom or whatever will work best and attach a 10ft handle to it to pull or push the leaves/branches off? Maybe put some grip tape stuff going up to the ridge so you can get up there then just push the junk off while working from the ridge? OR what about some magnetic shoes haha

Yeah, I've been trying this for years! Doesn't work. Too far, stuff too stuck on roof, too dangerous.

I like the magnetic shoe idea! Ha!

 

[olytdi]

I would just use a padeye at either end with a stainless cable in between, it can lie flat on the roof and you won't have any problem sliding your safety line from end to end.
You may want to consider using nylon webbing and taking it down when you aren't using it, how safe will that cable be in 10 years? That's how it's done on sailboats, and for exactly the same reason. Look up jacklines

I think we're thinking of the same general idea -- a cable across the peak that you can slide your safetly line along. I am familiar with jacklines. I'm not clear about what you're visualizing attaching the padeye to, however. There's really no anchoring area along the roof --that's why I was thinking of the pipes that would be bolted to the main posts with really beefy lags.

 

[reptilezs]

the cable across the peak loads the supports inwards and has to hold the fall. look up the American death triangle

 

[olytdi]

the cable across the peak loads the supports inwards and has to hold the fall. look up the American death triangle

Wow. I just google American Death Triangle. Sobering and thought provoking.

I think I'll be talking to the climbing experts at the local Alpine Climbing shop.

Thanks for that heads-up!

 

[kbs2244]

I don’t know if the American Death Triangle comparison works.
He is talking more of a sliding leg on “T” than a triangle.

I have never used his idea, but I have seen it done.
It is a confidence builder.
But I have never seen it actually save anyone.

 

[Spareparts]

A cable running across the ridge, sounds similar to a LIGHTING ARRESTOR better run some grounding wires from the cable to a ground rod. Your Utility Co should have some galvinized cable called Static Cable and used just for that grounding static electricity (lighting) might pick up a short piece for cheap they usually come in reels about 2 + miles long and should easily withstand any sideload 1 person could put on it.

 

[steve308]

Just send your wife up there

 

[superfish]

Back to the parking the truck idea. If you can't maneuver the truck to the right place why not construct a permanent anchor. One on each side of the building. This could be a buried "dead man" made of crossed beams. Just throw the rope over and pretend it's hooked to a truck.

I'll leave the details to you, I'm just the idea guy.

 

[elvee]

There are engineered fall protection systems designed for roof systems like yours. They mount into the trusses along the ridge line and have a continuous track for a connection point. Standard anchorage point needs to be rated for 5000 pounds per point for life lines. The galvanized pipe extensions will bend or shear long before you stop falling.

Look up a company called MSA Surety. They build a lot of fall protection gear.

 

[kert]

Back to the parking the truck idea. If you can't maneuver the truck to the right place why not construct a permanent anchor. One on each side of the building. This could be a buried "dead man" made of crossed beams. Just throw the rope over and pretend it's hooked to a truck.

I'll leave the details to you, I'm just the idea guy.

Or one of those pesky trees that is dropping stuff and preventing you from driving your truck back there.

 

[Stuart in MN]

What kind of trees are they, and what do they leave on the roof? Leaves, needles, pods? How about using a pressure washer to soften it up, then using a snow rake to pull it off?

Another thought is to get a couple ladders like roofers use to work on slippery roofs, like metal or slate - they have a hook at the end; you lay them flat on the roof and the hook goes over the peak.

If you have to walk on the roof, maybe get some broomball shoes - they have thick spongy soles with a suction cup-like pattern; they work pretty well on glare ice.

 

[ietech]

I am required to use fall arrest on a daily basis and it is very serious business. The wrong set up can be just as dangerous as falling to the ground.

Be sure to use a 5 point harness and a self retracting hook up. With a rope you could easily cut your self in two or the very least break your back from the abrupt stop at the end of a rope. See attached for Ideas GOOD LUCK.

http://www.fallprotection.com/

 

[CreekWV]

I think the term you might want to look up is Vector Pull, to calculate the load you would put on a fixed line like that.

Another alternative might be to put an anchor in the center of the roof, just off peak (using a vent flange to seal it), and then using one of the self arresting systems, or even a simple 14' tag line, that would keep you back from the edge if you slipped.

If you do a cable, You can get a piece of galvanized or stainless cable to length from places like Fastenal. Remember to use a steel carabiner, not aluminum, with steel rope.

This may sound odd, but pick up a pair of climbing or approach shoes with the stickiest rubber formula, like 5.10 Stealth or the like, you can. Will make a huge difference in your grip up there.

 

[reptilezs]

also use a shock absorbing safety lanyard if using static line or steel cable. you can also tie off with dynamic climbing rope. can also do a solid anchor at the roof and tie off with dynamic rope, then have a prussik cord or friction hitch to take up slack as you move around