Wednesday, May 8, 2013

Chapter 11 - First Floor Framing - Phase II

Chapter 11 – First Floor Framing
Phase II
My third video documents the raising of the south extension from the central stairwell box to the outside of the frame on September 27, 1997. At this point, the north extension has already been raised. These two extensions form the first floor portion of bent #2 and bent #3. The two other extensions, running east and west, completing the central “plus” of the first floor framing are actually two of the connecting girts of bay #1 and bay #3. Once the four extensions from the center stairwell box are complete, what remains to complete the framing of the first floor is the raising of the four corner posts and the beams that connect the corner posts to the central extensions that in turn connect to the center stairwell box. The eastern half of the first floor framing will also have joists to support the loft flooring. My fourth video documents the raising of the northeast corner post.
This is not the traditional way to raise a timber-framed structure. Traditionally, a timber-framed structure is raised in assembled bent units. Once a pair or bents are raised, they are connected with girts, joists and purlins. This method requires the raising of extremely heavy bent units and typically is done with a crane or many people. The use of the non-traditional spline connections, and raising one beam at a time allowed me to raise the frame without a huge crane or a large group of people to help.
To raise the extensions from the central box, I first raised the two outside posts with their splined crossbeam and braces strapped together. Once this assembly was standing, one of the two connecting beams was raised along with its two braces, followed by the other beam and its braces. I then strapped the outside posts together across the entire width of the frame and pulled them tightly together with come-alongs. After checking to make sure the entire bent #2 and bent #3 assembly was square and the outside posts were plumb, all of the joists were pegged. The same procedure was then repeated for the east and west extensions. As far as the first floor framing is concerned, the east and west extensions form bents that are perpendicular and identical to bent #2 and bent #3. In fact, all four corners are also identical to each other. Obviously, I am a big fan of symmetry.
After the experience of raising the stairwell box and the crane’s lift being barely adequate on top of 2-inch thick boards, I developed a new runner scheme. I decided that the stack of 16-foot long 6x8s that would someday become roof purlins would be useful. Laid on their sides, they were just as wide as the boards that I was using. Using the stickers that were under the timbers on the flatbed truck for cross supports, these purlins formed runners that raised the crane height about nine inches above the deck. Using four of these purlins, two for each set of wheels on the crane, the rails were wide enough (16 inches) that I could roll the crane forward without having to allow for the wider separation of the front wheels. They were also long enough that I could extend them over the side of the deck the three feet that I needed to hold the front wheels when the crane was raised to its highest position. The down side of this plan was the work involved. Each of these beams weighed over 250 pounds. Despite the effort it took to move these purlins to each raising site, get them positioned just right and getting the crane mounted on top of them, they solved all of my lifting problems. This method worked so well that I was willing to continue using the same four purlins as my crane runners all the way up to installing the peak purlins and king posts.
Now that I had some practice with a workable raising method, the raising of the east and west extensions from the stairwell box went smoothly and undocumented. By the time I had the central “plus” raised, I was running out of pleasant weather and time. It was into October; our first grandchild was due shortly and a host of family holidays were on the horizon. It was time to go back to Pennsylvania. With an incredibly heavy, army surplus, 25-foot square canvas tarp, I covered the center part of the framing. In spite of my Styrofoam job on the bases of the posts, I wanted an extra layer of protection for the precious stuff that was now residing in the basement apartment.

As I was trying to spread the monster tarp over the finished “plus”, I realized that I hadn’t taken any photos for Linda. I left my covered masterpiece and headed for Pennsylvania on October 31, 1997.

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