I'm building an extension at home to an existing flat roof extension. I've got the walls up to plate high now and am going to put a 8/12 pitched roof over the old and new extensions. The new will be a vaulted ceiling. The problem with the old extension is that the distance between the plates is 2 inches less near the main house than where it joins the new bit. As I'm going to cut the rafters myself I was thinking about the different options. 1 Keep them the same pitch and shorten each rafter which should drop the ridge about an inch and would mean bumping up the ridge tiles one end. 2 Cutting them all the same length and increasing the pitch a bit on each pair. 3 cutting them all the same and packing up under the seats of the rafters. 4 Making the seat cuts a bit higher each pair and possibly having a bit less bearing near the end. Do any of these seem any good or is there a better method? The new extension has a thicker wall 12 inches than the old one 10.5, but I know how to get round that I think. Thanks for any help. Waste of time me asking the chippies at work, most of them only know how to put in trussed rafters, and the ones that do know will only say ' sorry mate, don't give free advice'.