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The 10m space between the front and the rear gable walls meant that it was not possible to use a single piece of wood as a purlin. The original oak roof used 3 purlins on each side of the barn, joining on the A-frames. I used 2 purlins on 5.7 metre purlins on each side of the barn. The join is at the centre of the barn between the A-frames.

These 5.5 metre are not 225cm x 75cm piece of wood are not too difficult to carry on the ground, but manoeuvring them in to their final position was not an easy task. As soon as we had fitted the 2 purlins to the front gable we moved the 2 remaining purlins so that they were resting between the 2 a-frames. We were then able to use these 2 pieces of wood as walkway that allowed us to screw the rafters for the centre section of the roof to the ridge board.

The new purlins are larger than the originals, so some of the back gable wall is removed to accommodate them.

In order to fit a gable ladder and prepare the space for the purlins in the back wall we needed to erect some scaffold, the back wall is 6 metres off the ground at its highest point, and about 5 metres off the ground where the purlins fit into it. We managed to shuffle the purlins that had been resting on both a-frames on to the back a-frame and then swing them across on to the scaffold. The lifting of the purlins into there final position was then pretty straight forward. Fitting the rafters to the ridge board in this back section of the barn was more of a problem. We had to build a scaffold tower up to the height of the ridge to fit fit the last 2 rafters.

The new wall plate is bolted on to to the orginal oak wall plate

Rebuilding the top of the gable wall around the purlin

The ridge board seems straight!