A Roof Raising Tale

Raising the roof is a scary process... until you get into it. Then it only seems natural.

When we started down this journey, we decided we didn't want to build a castle, only a comfortable vacation home on wheels. Neither Teri nor I are 6 feet tall, and the kids will not be that tall, either, so the standard heights in the bus would have worked fine, if we had stuck with the original KISS plan. However, shortly after purchasing the first bus, I met Dave and Karin, and went to look at the MC8 they are converting. He had raised the roof, and installed an oversized window on the right side. When I walked into his coach, I was overwhelmed by the openness of it and the sense of space. I could stand full upright and gaze out the window, or be sitting comfortably on the chair and still have a totally unobstructed view. And the ceiling was so high!! It was an epiphany (how's that for use of a big word). I knew immediately that I'd have to raise the roof!

This realization allowed me to make a few more decisions about how to complete the conversion. Firse, it meant that I'd not be keeping the rooftop air conditioners, which didn't bother me too badly. I don't particularly like the looks of them on top, anyway. There's just something about a clean roofline that appeals to me. So ducted basement A/C is the way we will go.

Second, it meant that I would have room in the ceiling to add ductwork for the basement air conditioner, more insulation, and possibly a couple wire chases. All of which are positive side effects of the roof raise.

And third, it meant that I would have room to put the radiant floor heating system in that I wanted.

Of course, after doing some figuring on how much space we need for the above options, it also became apparent that after I installed the radiant floor system, and the extra ductwork and insulation in the ceiling, the 8 inch roof raise would actually yield about one inch in increased head room! Well, as I said before, none of us are 6 feet tall, so I guess I just justified it all, right?

So. onward and upward with the roof raise....

To get to this point, the bus was stripped inside and out and then blocked up level, front and rear.

The luggage racks, washroom, interior air vents, ceiling panels, windows and exterior caps had already been removed (see related pages elsewhere in the site). Preparation for cutting the vertical posts and doing the actual raise were now in full swing. The first step was to mark all the uprights so I could measure accurately across the cuts to make sure the raise was exactly 8 inches. Using a scribe (fancy term for a broken screwdriver sharpened on a grinding wheel), I marked several lines at 3 inch intervals on each post. The plan would be to cut between the lines, and measure the difference between two or more lines. As the roof is raised, the lines will get farther apart. By calculating the change from the original measurement, you get an accurate measurement of how far it has been raised. When the change equals 8 inches, you stop raising it and secure everything by welding pieces of steel material into the gaps in the vertical posts.

The next thing to do was to establish a reference to which I could check to make sure that nothing shifted while raising it. The bus had already been blocked up, front and rear and was quite stable. Using a plumb-bob attached to an overhead frame member with duct tape, I estabilished 4 points of reference. To mark them, I drove a small drywall screw directly into the floor, centered under the plumb-bob. I then marked the screw heads with paint, to make it easier to find them later on. Since I only have one plumb-bob, and could not leave it attached to the overhead beam for very long, I needed to be able to accurately relocate it to the exact spot on the beam for future checks. Using a can of spray paint, I lightly sprayed over where the string was attached to the frame member. When I removed the tape and string, there was a discinct image of where the string had been. Now I could replace the string in the exact spot later on.

I had spent a lot of time in the past year thinking about the best mechanism to use to raise the roof. Many use screw jacks from auto junkyards. Some use port-a-power units. Both seem to work very well. Both require supports to keep the roof from moving either sideways, or front to rear, and both require safety supports be positioned as the roof raises. Fine adjustments can be made with either method. The third method, and ultimately the one I chose to use, is the all-thread method.

Some time ago, I had come across the website of a fellow in Utah named Randy Schreifels. He had purchased a wrecked GMC 4905 from Western Wyoming College in Rock Springs, WY. Of course this piqued my interest as Rock Springs is just 130 miles from "home", and Utah is home to many of my family members. Anyway, Randy had raised his roof 10 inches during the spring of 2000. In his photo outlay, he shows a set of brackets consisting of two pieces of angle iron bolted to the vertical posts, and separated by about 4-6 inches. Each bracket has a hole drilled in it. The vertical post is marked between the two brackets, and cut. After cutting the post, a piece of all-thread rod is passed through the two brackets and secured with nuts (4 total) to the top and bottom sides of both brackets. One set of brackets and all-thread rod is attached to each corner of the roof, all the nuts are secured, and the roof is then cut free of all remaining posts and constraints. To effect the raise, all that is necessary is to crank on the top lower nut. As the nut is screwed up the all-thread rod, it forces the bracket above it to move upward, thereby raising the roof. By working from one bracket to the next in sequence, and only raising a half inch to an inch on each pass, one person is able to raise the entire roof by himself, in a very short time period. When all posts are secured with new steel filling the gaps, the all-thread rods and brackets can be removed.

Sounds simple enough. How will it work in actual use?

Having already removed the interior panels, I was able to view the extent of the corrosion in the frame members of my MC9. I had already come to the conclusion that significant work would be required to repair the damage, and it would probably be best to just cut out the old frame, and fabricate a new one. I could then frame in for new windows where I wanted them, add diagonal bracing, and set the vertical posts at the proper width to accomodate my new skin material. To that end, I decided that rather than fill the voids in the old vertical posts created by raising the roof, I would weld angle iron directly to the posts to act as guides, and then simply weld them solid to the posts for support while replacing the frame.

I started preparation by cleaning the old caulking material from the outside of each vertical post using a wire brush on my large angle grinder. This was necessary to allow me to weld the brackets and supports directly to the posts. NOTE: This tool is extremely dangerous as the wires tend to break loose and become very sharp projectiles. It is imperitive that you use high quality safety glasses with side shields, or more preferably, a full face mask, when using this brush. I had several of these wires stick in my clothes, and one impaled my arm, resulting a large bruise around the point of entry.

Side note: As I cleaned the vertical posts, I noticed that one of the original frame members just behind the driver's window had cracked at some point in the past. It was nearly severed. Here's one more reason to justify the work of raising the roof and re-framing the whole bus. I can beef up the frame where needed and add cross bracing to strengthen it and add some stiffness.

A slight variation on the theme was now in order. Since I was not going to fill the gaps after the raise, my cuts didn't need to be very accurate, or straight; only between the lines. This allowed me to complete the incision using my large angle grinder fitted with a 7" cutting wheel. This setup makes quick work of slicing through the steel ribs, though the blades don't last very long. I'm considering purchasing stock in the company that makes them. Also, since I was using a big, bulky grinder, I decided to cut each post first, and then attach the brackets. Again, let me stress that proper safety precautions need to be taken when using this setup. The cutoff wheels have a tendency to bind in a cut due to shifting of the steel members as they are cut. Chunks of the wheel can disintigrate in a split second, blasting you in the face with the debris. Wear proper eye and ear protection at all times.

We were now ready to cut the posts. They had been cleaned and marked, and the brackets were ready to be attached. Here's a final look at the original height.

The first post was cut through using the grinder / cutoff blade combination.

Next, I clamped two pieces of 1" x 1" x 1/4" angle iron and a piece of 2" channel iron to the post below the cut. These would be welded to the post, and would act as guides to keep the roof from shifting while being raised.

The angle iron and channel iron were then welded to the post, below the cut, forming the channel in which the upper part of the post would slide. I welded the angle iron to 8 posts, and the channel iron to 4. 4 posts in the center and the end corner posts were left unsupported.

After all the support brackets were welded to the posts, I then welded the jacking brackets on to the four corner posts. 3-foot all-thread rods were inserted into the holes in the brackets, and washers and nuts were added. The nuts were tightened up and a slight upward force was created on the posts. This would help minimize the binding on the cutoff blade as the remaining posts were cut.

With all the jacks and supports in place, I then cut through all of the remaining posts, leaving only the front-most and rear-most posts attached. These would be cut immediately prior to the actual raise, along with the front and rear cap supports.

The Day Of Raising Has Come

After a one week delay due to uncooperative weather and my not getting everything ready in time, the morning of the actual roof raise finally arrived. It was a gray, overcast day, with a slight breeze and a hint of possible rain. I hoped the weather would improve as the day progressed.

I removed the front and rear caps so I could do the final cuts through the cap supports.

You should have seen the neighbors looking when I climbed up on the roof with my big grinder and started cutting through the final supports! They all think I'm nuts anyway, but this surely confirmed any doubts. The neighbors across the street who don't normally talk to us and therefore have little first hand knowledge about the project were having a birthday party for their child. Guests were arriving all the while I was cutting the cap supports. As each one would arrive, you could see them being greeted by the host, and then they would each turn to look in my direction. Often, they'd point my way. I didn't have to hear the words to know what was being said. This went on all day. At one point, my wife saw a group of older men clustered near the corner of the property closest to me. They were all talking and looking my direction. She said she could just tell that they would rather have been at my house than at the birthday party. None of them ventured across the street. Too bad for them.

In the weeks prior to the roof raise, we had noticed an increase in slower moving traffic past our house, and as the day progressed, it seemed to intensify even more. It appears that the people are driving slower because they may have suffered some sort of neck injury that prevents them from looking straight ahead. Funny, though, that the injuries seem to be related to the direction they are traveling, as all of them have their heads turned towards my side of the street. I do hope they all get better soon. I'd sure hate for one of them to run off the road or cause an accident because of it.

I had unpacked my fiberglass parts and laid them out on the yard so I could get some measurements to confirm where I needed to cut the supports. It was probably not real easy to tell just what was happening, so there was certainly a lot for folks to discuss.

The front and rear cap supports were cut through, leaving only the corner posts holding the roof. It was getting scary, now, as I began to wonder just how heavy this roof really was, and if 3/4" all-thread would really support it, and how much wind would it take to make this thing fly!

The front corner frame supports and gussets were next to be cut. Of course I took photos of them before the cuts, and forgot to take any of them after. However, you can see them later on as the roof is raised.

Finally, the rear corner posts were the last to be cut. It took me several minutes of checking and re-checking to see that everything was in place before I could make those final cuts. The wind was blowing more than I had hoped for, and the skys were threatening a storm. I was not wanting to get half way through the raise and have a big storm blow in, so I was taking my time to see how the weather would shape up. So far, there hadn't been much change all morning. I checked the radar loop on the computer, and saw that most of the overcast I was seeing was part of a system that for the most part had just passed up, and the radar indicated nothing coming in for about 200 miles. I figured I had enough time to get it up and welded in place, so I made the decision to go for it and cut through the last posts.

Teri came out to help, and with her on one side, and me on the other, we began the process of cranking it up. We started with a half inch on the rear posts, and moved to the front and matched it there. It went smooth, and everything seemed very secure. Back to the rear, and up another half inch, followed by another equal amount on the front.

Cool! We're up an inch!

We then started moving an inch at a time, starting in the rear, and matching it in the front. I think the all-thread on Teri's side must have had different threads than my side because she always beat me to the mark. Maybe I was just watching everything else, and not turning the nut fast enough.

I didn't time the actual raise, but it did not take very long. I estimate it was probably between 30 and 45 minutes to complete the full 8 inches.

The only problem we encountered in the raise was with the gussett above the driver. When I cut it free from the roof beam, I didn't pay much attention to it, and so ended up with a cut that slanted, with the top part ending up farther rearward than the bottom part. This had the unfortunate side effect of causing the lower roof rail to bind as it tried to pass on the way up. It was not immediately obvious this was happening, until I heard a pop as it "gave". Thinking all heck had just broke loose, we immediately stopped to figure out what had just moved that shouldn't have. I soon discovered the problem, and found the remedy was to periodically pry the two pieces apart with a large tire spoon. This allowed them to pass until they were clear of one another.

We carefully measured and fine tuned each corner, setting them each to exactly 8 inches. Then, we clamped the angle iron brackets tight above the cuts, and welded them to the top of the posts.

It Is Risen!!

We were then able to stand back and view our progress.

Getting to this stage was very time consuming. It has not been exceptionally difficult work but it was quite daunting. However, now that we've raised the roof, it all pales in comparison to what lies ahead! Now the real fun begins... reframing the sides.

Tips and Tricks

Angle Grinder Cutoff Blades
The large angle grinder fitted with a 7 inch cutoff blade works very well to slice through the steel ribs. A fresh blade will go about 3/4 of the way through the support. With the outside skin removed, this is sufficient to allow cutting completely through using a pass on the inside, and a pass on the outside. These blades wear down quite rapidly, though, and the grinder housing and blade guard limit the amount of usable blade to about 1 1/4 inches before it will no longer cut. I averaged about one large blade to remove a single vertical post (top and bottom, side rail, and seat rail; 6 cuts total). I found that if I use the blade until it no longer cuts on my big grinder, the remaining blade is about 4 1/2 inches in diameter. Since I also have a 4 1/2 inch angle grinder which uses the same size arbor, I simply take the remaining blade, and mount it on the smaller grinder to get double duty out of it. It works great, and the smaller grinder is somewhat more versatile in certain situations. Now if I could only find an adaptor that will allow me to mount the remnants of my 14 inch cutoff saw blade on my angle grinder. It uses a larger arbor so the blades will not fit the angle grinder.

Locking Pliers Clamps
I typically buy top quality tools. My philosophy is that spending top dollar for tools is money spent one time for tools that last a lifetime. However, on rare occasions, I will buy cheaper tools that I probably won't use as often, or that may be expendable through normal use. It usually depends on what the tool is, how often it will be used, how hard it will be used, how much money can be saved, where the cheaper tool was manufactured, and other relevant issues.

Vice-Grip brand makes the best locking pliers and locking pliers clamps without question. They have been a fixture in my tool set since before I bought my first portable toolbox at age 16. Because I use locking pliers a lot, and need them to be rugged, I would never buy cheap imitation locking pliers. That being said, I must admit that the clamps I used for positioning the angle iron guide pieces for welding are not Vice-Grip brand clamps, but cheaper imitations made in Taiwan and China. Since I will only use them for occasional welding, I figured they would be fine, and I could save a few dollars. They were on clearance at the local home improvement center, and the price was about half the regular price and about one-fourth what comparable Vice-Grip brand clamps would have cost, so I bought all they had (4 sets of 3 sizes each).

These clamps have been invaluable to this job, and buying Vice-Grip brand clamps would not have been wasted money. However, after using them, I have no problem recommending the cheaper imitations which are made in Taiwan. They have performed exceptionally well for me. I would, however, recommend you stay clear of the ones made in China. They do not work well and are very hard to open. Also, you should have a minimum of six 8 inch clamps on hand to do similar frame work. Smaller and larger clamps can come in handy, also. You can't have too many clamps.