I posted in this forum because of the recent threads about roofing angles...it might be better suited in the Exterior Details forum and if it gets moved because of this my apologies...

I'm doing a lot of cedar exterior trim. On a couple different models we have dormers with square cut tails. Obviously a dormer with a plumb cut tail just gets a level cut where it meets the main roof...with the square cut tails it gets a level bevel.

I'm not sure how to calculate this compound angle. I've been doing it using the cave man method of holding a fascia board up and scribing the angle/trial and error. This works but isn't really the way I like to do things. The cedar soffit ply also runs back to the main roof on a compound angle.

Would anyone be willing to help me through the calculations to figure this angle out? I use a Construction Master IV...but I'd welcome any methods. The diagram I'll post is of a 10/12 dormer on a 7/12 main. There are a few different combinations but I should be able to figure the others out once I get this one.

Thanks.

Tom

(I'm trying to upload a diagram (bmp sized to 640x480 - Irfanview) but I get a message saying "document contains no data".....any quick help or suggestions to help me upload a diagram?)

I'm doing a lot of cedar exterior trim. On a couple different models we have dormers with square cut tails. Obviously a dormer with a plumb cut tail just gets a level cut where it meets the main roof...with the square cut tails it gets a level bevel.

I'm not sure how to calculate this compound angle. I've been doing it using the cave man method of holding a fascia board up and scribing the angle/trial and error. This works but isn't really the way I like to do things. The cedar soffit ply also runs back to the main roof on a compound angle.

Would anyone be willing to help me through the calculations to figure this angle out? I use a Construction Master IV...but I'd welcome any methods. The diagram I'll post is of a 10/12 dormer on a 7/12 main. There are a few different combinations but I should be able to figure the others out once I get this one.

Thanks.

Tom

(I'm trying to upload a diagram (bmp sized to 640x480 - Irfanview) but I get a message saying "document contains no data".....any quick help or suggestions to help me upload a diagram?)

## Comment