I have a roof (my own house) I am going to raise soon to create living space where there is now attic space. I can save a good deal of money, time and exposure to the elements if I hire a crane to just lift the entire roof up and place it on pre-made kneewalls.
I have 25 years experience in residential construction, but have never done this particular project. What I have in mind is this;
The ridge is 16 feet long and the rafters span an 18 foot wide addition/family room. I would put collar ties on every rafter a good deal lower than normal to stiffen the bottom of the roof assembly and plywood gussets right up to the ridge board to keep the tops of the rafters tight to the ridge.
I would lag bolt 4x8s to the underside of the rafters on either side of the ridge about 3 down and punch 4 holes in the roof for lifting cables that would be attached to a spreader bar on an appropriately sized crane.
Lift the whole thing up, swing it to the side while the knee walls are stood up, braced off, then set it in place. Button things up and pop a beer.
I realize no one wants to say yea or nay, because of the danger involved, but how about some of your thoughts from those with similar experiences? Thanks in advance.....
Yes this can be done. I remember reading about someone doing the same thing and it worked out great. I think I read about it in JLC oe Remodeling Mag. If you are in the Detroit area, I would love to watch or help. Good luck and let us know how it goes!
I think I could frame, sheath, and shingle an 18x16 gable roof in half the time I could do all the prep work to lift it off the house, and there'd be no chance of dropping the thing and ruining the roof and the house.
With trusses, I bet I could do it in 1/3 the time.
I'd save half the material costs by not hiring a crane too.
Wayne, you didn't say what part of the country you're in, but in my neck of the woods(Boston), there's a company called High Tech Dormer, they specialize in doing just what you are attempting.My electrician did a job for them and except for the rest of the job, the lift-off and put-on worked quite nicely, in other words they were good at the latter but as GC's they left a lot to be desired, I think they should have stuck with the lifting portion alone. It is a workable solution AND can be cost effective since you don't have to frame a new roof system, I also think the prep for lifting can be accomplished in a fairly short time frame, something like a day or so depending on the size of the roof. Good Luck and let us know how it goes!
Perhaps you could Ryan, but there is also the demolition to think of not to mention the dumpster cost. If done properly, it is a safe operation, I'm quite sure of that, and I'm also convinced it will save time and money, the latter of which is always limited. A half day for a crane is around $400. Not much more than a 10 yard dumpster and no demolition work.
Wayne,This does work and you will save a bundle (Pun intended) if you take the time to plan and do it right.If you have some space on the ground where you can build your new walls first you can save some time and the crane will lift them in place.Be aware of plumbing vents and electrical masts! You may need to have that mast/drop rerouted before you begin.One other thing to check for is wires that run on the rafters or plates. Be careful to get all of them removed.Take lots of photos! It is a kick.
My boyfriend and I are buying a house and are very interested in your idea. We have no idea where to start looking as far as contractors and estimates are concerned or if Dormering is better Please let me know how it works out and what your cost is. Any pertinent info would be great for us young first time homebuyers looking to save some cash!! Thanks, Kellie
We're in north carolina want to change the look on a very low country looking home. Raising the roof on the attached garage would enable us to give the look we want, plus provide a better quality space in the living space that's already there. Please let us know how your project turned out. Real well I hope.