or, slide the safe to the bottom of the stairs on towels or a piece of carpet. Put, two long planks on the stairs. lay the safe on its back on the planks and pull it up with a come along or several buddies.
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We're now a two FJ family
Black Diamond and Black Cherry
Moving a 550lb. safe? Regardless of how you finally do it, it promises to not be the best day of your life.
I have a 350-pounder or so that I would love to move to my basement office but I just don't trust my moving skills nor the weight capacity of my basement stairs to even try so it stays where it is.
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"They responded to the other point of view with a recently invented little noise, something between tsk-tsk-tsk and hissing. It's the noise the kind of people who own more than one cat make when the kind of people who own more than one gun light cigarettes indoors." - P.J. O'Rourke
I've moved some fire safes up stairs.....when I was in my twenties, lol.
The stair climbing hand truck is the way to do it, or as was already suggested too, lay it on it's back and slide it up. I don't know how the house is laid out, but a come-a-long moutned to a 2x8 behind a door frame sounds like good insurance if you do slide it up.
For Chrissakes, please speak to an Architect about where you plan to put it when you get it up there.