"Never ask a French builder to give you a hand after lunch". I did but think i still have my teeth. Mind you I have a fat lip and was spitting blood for an hour. Schoolboy error! My "ami" had a bit of a wobble and while we were 4m up in the air dropped a 6m long 3"x8" which bounced off the roof and smacked me in the mouth. Ho Hum. Anyway here is the progress; purlins are up and the roof is braced ready for rafters.
roof still with temporary bracing
And some more permanent cross bracing
Next its the rafters and then some slates. The spacing of which is up for some debate. In France all slates are held on with wire clips not nailed. The clip hooks over the batten and supports the bottom of the slate. The next clip above holds the top of that slate and the bottom of the next slate above. The spacing of the battens depends on the size of the slate and the size of the clip. Easy, so batten spacing is derived from the following formula:
length of slate - length of clip - a bit / 2
The "bit" above is the amount you want the top of the slate to sit past the top edge of each batten, usually about 5mm. The divide by two is because there are two battens supporting each tile. So in our case we have 320 mm slates and were going to use 90mm clips
320 - 90 - 5 /2 = 112.5mm spacing