Wednesday, May 8, 2013

Chapter 12 - Loft Framing - Phase II

Chapter 12 – Loft Framing
Phase II
Linda takes her jobs very seriously. I told her that the timbers that were sitting in drippy humid Pennsylvania needed to be turned from time to time so they would dry evenly and not get moldy. I was only half serious, since most of those timbers were much heavier than she is. She also learns very quickly. She had her favorite stick (lever) and rolled each timber regularly, kept them covered with tarps, cared for them like her children and I found them in perfect condition.
Meanwhile, Keith, my trusty sawyer was busy making oak boards. He had about six bundles of boards in his saw yard that I could have for less than a dollar a board foot. That seemed like a lot of wood, and at the time, what I would use all those boards for was only vaguely clear. I figured that there were enough boards in his pile to cover the first floor twice! Though these boards were not the best grade lumber on the planet, the price seemed right. Besides, we had to fill a flatbed with something, and keeping Keith happy was a very good idea. As I write this, I’m running out of boards and have no idea how I would have finished this house without them.
In a few weeks, I had all the timbers banded and all those boards un-stickered and re-stacked into nice tidy bundles. After two previous flatbed loading experiences, I basically knew what I was doing this time. Having learned that I was not very good at estimating timber weights, this time I had the driver take the truck to a scale the day before he was to leave and before Keith took his backhoe home. Sure enough, the load was over weight, and a few bundles of boards were left behind.
By now, Linda was excited about the idea of moving to Colorado. She had her house up for sale and knew exactly what was going with her. The children were less enthusiastic about mom moving away. I think they realized that she was serious when we parked a moving truck in the driveway and started loading the left behind boards and most of Linda’s precious stuff inside.

On July 15, 1998, Linda and I were again cruising across the country, this time in a big new moving truck. This load included all Linda’s precious stuff and even a mattress that we used as a motel room at truck stops. Most folks seem to think that that was pretty weird, but it made perfect sense to us. Once we got to Colorado, I went looking for the fellow in town with the forklift. I had to resort to the rental store, which fortunately had exactly what I needed. Unfortunately it did not come with an operator. This did not seem like a very good time to learn how to operate a forklift but it was certainly exciting. Actually it was not that hard, I’ve had a lot more trouble mastering a backhoe.
With all of our stuff either put in the place that Linda had planned for it in the apartment or stacked in the corner of the workshop under tarps, it was time to get back to work. By now it was August and if I was going to get the frame done in keeping with my chiseled in oak date of “1998”, I had to move right along. I had already done the hard part of the loft level framing, the part that seemed the highest in the air. The back half also had the advantage of joists to stand on. Compared to the open bay #1 area, this end was like working on the ground! By September 16th, the loft level was finished.
 All I have are photos of the raising technique for the back half of the loft raising that I developed after quite a bit of practice. After lifting the two queen posts and their bay beam to the loft level, I assembled and strapped together the unit along with the braces and the spline for the middle bay beam. This process insures that all of the joinery fits before the unit is lifted into place. The base of the crane, standing on runners, is attached to a first floor beam behind it with an orange ratchet strap. As the crane lifts the assembly, the post bottoms slide and catch on the post bottom blocks stopping the assembly from sliding toward the crane. Once the posts are stopped from sliding toward the crane, without the strap to hold the crane in place, jacking up the crane would simply pull the crane forward on its runners under the assembly. When the assembly was beyond half way raised, most of its weight was directed to the bottom of the posts. Because most of the weight is now off the crane, the ratchet strap can be shortened easily, pulling the crane backward on its runners and continuing to raise the assembly.
The crane runners in this raising are only 2-inch thick boards instead of the 6x8 timbers that were used for this raising in bay #1. That is because the bent beam is higher than the bay beam that the crane is attached to so the crane didn’t need to be as tall to lift the assembly. Also, in this bay, I had joists to support the center of the boards that would have bent under the weight of the crane over the open area in bay #1.
There are two blue ropes attached to the bay beam and the first floor framing that are tied to the right length to prevent the assembly from being pulled over too far beyond vertical. Continuing to shorten the orange ratchet strap pulled the crane backward and the assembly the rest of the way to vertical. Once the assembly was upright, the other ends of the blue ropes are attached to the first floor framing on the crane side of the assembly to guy the unit in place. The crane can then be disconnected.
Despite the fact that I carefully measured and cut the lower rafters, I raised them in opposite pairs without pegging them so that I could fractionally adjust their fit after they were in place. Since the queen posts were not pegged to the frame, but rather resting on the beams underneath them on their blocks, I could still move the queen post and beam unit in the direction of either lower rafter a bit. Once the joinery of both lower rafters were held tightly in place with straps wrapped around the first floor framing, pulling them downward, I compared the fit at the tops of the two queen posts. I made the two rafters fit the tops of the two queen posts by pulling down on one rafter and loosening the other rafter. The two queen posts could also be slightly moved to help this fitting process. I had already done this alignment process with the bent #1 and bent #2 lower rafters. After adjusting the bent #3 lower rafters, I also made sure that the tops of all of the queen posts were aligned along the axis of the frame. Making sure that all of the joinery fit together tightly, I then pegged the rafters at each end and the tops and bottoms of the stub posts. This rafter and stub post pegging locked the queen post locations on top of the beams in place. I then repeated this process for the bent #4 lower rafters.
I tried stretching a string along the tops of both sets of queen posts to check their alignment. This didn’t tell me much because the 40-foot length allowed the string to sag too much. The best I could do was sight along the outside top corners of the queen posts and assure myself that they all lined up.
Now that the rafters and queen posts were all firmly in place, I could install the purlins connecting the rafters together. The purlins for bays #1 and bay #3 are nominally 14 feet, 8 inches long and the center bay purlins are nominally 8 feet long. I, of course, measured each span before I made the purlin to get a precise fit for each purlin. All of them are 6x8 timbers with un-housed dovetails at each end. The purlins are spaced 4 feet apart, from center to center so that any standard roofing plan would work. At the time, I was thinking in terms of stress-skin panels that come in 4-foot wide sections or could span 4 feet. Each bay has six purlins connecting the lower rafters together, three on each side of the queen posts. The north center bay is slightly different; its top purlin is omitted. This difference is to provide a space for a chimney to pass through the framing.
The last time that Linda was here, she wondered why I was cutting off all of the peg ends. Because I was reasonably athletically inclined and knew how to use a hand saw; cutting off the peg ends was the job that I always wound up with when I worked with Ed. It was just part of the process. Linda thought that I should leave the peg ends sticking out of the frame. They would come in handy to hang stuff on! So, I quit cutting off the peg ends, except when the mallet mangled them beyond hope.

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