The spring as finally sprung just in time to assemble this neat annex. The footprint is square and was ideal for creating a square pyramydial roof. This frame is based around  8″ x 8″ (200mm x 200mm) timbers, for continuity the sole plates, wall plates and primary rafters are all this size. 

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This is a free standing frame with a solid roof, windows to the left and double French doors to the face we are looking at. The rear studded wall will have a couple of windows, but be mainly solid, as will the roof. 

square_pyramid1

As can be seen above, the roof has four opposing curved braces to the primary rafters, all jointed to an octagonalized (is that a word?) king post, using massive lambs tongue chamfer stops. The primary rafters take priority and a fully tenoned to the king post, whilst the hip rafters have a V-shaped oblique saddle cut that sit nicely in the available space (there’s a lot going on at the apex!).

square_pyramid4

This is the foot of the hip rafter, once again a tidy saddle cut into the corner. This also shows up the lambs tongue chamfer stops that adorn the remainder of the frame. The sun shading here also shows up the subtle detail of the hand-planed finish. 

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The shadow here nicely shows up the contour of a face-halfed wall plate scarf, placed in this position for the structural benefit of limiting horizontal deflection. 

square_pyramid3

Finally, here we have something I blogged about earlier. Ovolo chamfers with a regular stop. Note the wall plates in these positions are jointed with a edge-halfed scarf, which is more suitable for the dovetail joint on the tie beam.