This roofing system joins very specialized elements. The eave girders run on top of the columns on the outer walls. The rafters are connected to tic beams called the rainbow beams. The rainbow beams arc supported by the cave girders. The supporting point of the rainbow beams is determined with a tool called the rainbow board (hikari ita). The basis for the roof support system lies on the saddle point (toge). The saddle point is at the intersection of the bottom edge of the rafters and of a vertical line perpendicular to the center line of the eave girders. Often this point is located above the eave girder in order to avoid weakening of the same. The rainbow beam has a dovetail shape at the end which connects onto the eave girder. A groove as wide as the rainbow beam is also cut into the eave girder to give full support to the rainbow beam. This system has to be made strong enough to support the roofing load and also roofers, who frequently hang onto the tic beams during erection or use them to lift loads. The full width groove protects against splitting of the tic beams. Another groove is sometimes cut through the top of the rainbow beam to receive the rafters.
900 from the era girder np to the **st root a/lms
Bering board (mentoban) and rafter; rainbow beam, column and eave girder
O Wall framing column head: tenon and mortise)
€) A rafter is installed on the top of the rainbow beam.
O The rainbow beam connects on the girder through the kabuto dovetail system.
O A covering board completes the kyoro system.
From left to right: rafter, girder, column, tic beam
Ranbo* oeam(t>e beam)
CONNECTING JOINT 10
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There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.