Roof rafter tie rods3/28/2024 This definitely worked on a smaller home (only 24' wide) with a somewhat mild pitched roof (8/12). I also used these special bulkhead washers which meassure about 3" x 3" to keep from sinking the alltread nuts while they were being tighten. Soffits had to be removed to allow access for tightening alltread nuts and we also had to cut a hole in the gable end to slide in cribbing timber. We left the alltread in place to act as subsitute collar ties and propped the ridge off the cribbing that was also left in place. Lots of creaking and constant checking but we eventually got in straight in 1 day (with two days of prep). Basically my helper just added a few pumps to each jack while I went back and forth adding a few turns to each run of alltread. Several jacks were used to put upward pressure on the ridge while the nuts on the alltread were tighten.a little bit on each run of alltread (I believe we had 16 runs altogether). Cribbing was used along the center of the span and beneath the ridge (we were directly above an interior wall that ran down the center of the home). These ran the 24 foot span to the opposite top plate. We used 5/8 alltread with couplers at every 16 inches along the top plate. The seperation along the joints of the ceiling rafters was very apparent. The previous owner/DIY/ whatever made the assumption that the ceiling rafters would act as collar ties and they probably would have had the ceiling rafter runs (2 12 foot runs over the 24 foot width of the home) been locked together by more than a handful of nails. Had about a 2" sag along the center of the ridge line. Collar ties were removed at some earlier point and after a few years, the walls bowed and the ridge dropped. Keep in mind we want cathedral ceilings.or close to it. Since I want to secure the roof when I make this garage rnovation, please let me know if this seems structurely sound. However I am concerned about the support in the middle of the rafters and was going to put 2x4 blocking in the middle of each rafter. This will give the room a more cathedral ceiling look. However, I am going to place the collars beams flush against the ridge.as high as they will go.they will be small collaer beam made fron 2圆 boards. Please let me know if this will be structurely sound: I am going to put the collar beams connect EACH rafter. Since we want a high ceiling (somewhat cathedral) and not a lower Vaulted ceiling I was think of doing the following. Each rafter is about 14 feet long slanted appox 38 degrees. Presently there are only 3 collar beams attached to these rafters. There 8 roof rafters (16" on center) on both sides leading to a center ridge board. We are making a bedroom into Cathedral ceilings. I took out the ceiling joist which were only 2x4's. If it's like a normal house around here, it may fall on bearing walls that go down to the central beam that sits on columns to the footings. If adding the dormer and building a temporary wall to hold the ridge while converting it to a beam, it goes without saying but I'll say it anyway, check the bearing where you're building that wall, make sure it's adequate down to the footing. If the sidewalls are really bowed out, then I'd expect the joists are losing their bearing, and I'd be concerned about falling ceilings (or rather wonder why they haven't started to fall already) and also would expect great difficulty in pulling the walls in with tie-rods and turnbuckle because the joists may be hitting the sides of top plates. Or, like Tim asked, is the roof sitting on a kneewall in some kind of cathedral or semi-cathedral arrangement? Just to get a better picture. I'd like to know from pullen what is going on with the attic floor joists - assuming they run as I'd expect in the same direction as the rafters. I would hate to start another collar tie argument, but I would be interested in knowing what residential building code requires collar ties in the upper third of the attic space and/or requires them in high wind areas. They are required to be "as near the plates as practical” which cannot be construed to be in the upper third of the attic space so they are not collar ties. I have seen many books that show the use of collar ties as a standard practice but I have never seen a building code that required them unless you count “rafter ties” required by CABO (predecessor of the IRC) serving to tie top plates together when attic joists do not run parallel to rafters. These collar ties were not originally intended to resist the spread of exterior walls or resist wind uplift although they may have served those purposes to some degree. I have renovated a lot of them and have often been asked to remove or raise the ties. Historically that was their purpose which accounts for so many older homes having under-sized rafters. I did not intend to recommend the use of collar ties to reduce the size of rafters in new construction.
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