Interesting detail on the Deerfield barn, as far as the common rafters resting on a purlin. Like I said, all the CG barns I've seen here do not have common rafters at all. The date for this barn of 1851 or 57 is later than the 2 I've been posting pictures of... I wonder if this led the builders to the common (and sawn) rafter choice? Not even a birdsmouth/crowsfoot on them...
Anyway, it's unique... no two barns are the same, are they? That's what make it interesting, I think.
As far as the presense of purlin or common rafter methods throughout New England, Thomas Durant Visser's book "Field Guide to NE Barns and Farm Buildings," also gives a map on p.14...
All of New Hampshire is purlin teritory according to his map. But the map also says it depicts an 1840 time-frame... Neat barn. I've not seen that roof system before.
