28/08/08

Yesterday we did a truncated hip on one of our hips on the roof we used for the dormer window. This is where the hip gets cut back which is determined by the jack and then 2 hips come off that. I found this really difficult to get my head around to start with but once i got my head around it it was actually pretty easy. To start with we worked out the spans which are measurements that are right in front of us. Next we worked out our basted hip constant which was rafter constant+normal hip constant divided by 2. Once that was done we cut the jack and we worked out and cut a hip. Using the basted hip we got the height of the jack right so we could mark the hip and cut it where the jack landed. Then we shot the jack into the hip and got the 2 basted hips on. then we had 2 more jacks to get on. i was surprised to find that the top cuts for the other 2 jacks where exactly the same as the hip cuts.