Shed Roofs and Height of Walls

[Hanna]

Hi

I am using Home Designer Pro 2014 and currently doing an en-suite bathroom with a shed roof, I have managed to produce something that looks like a shed roof but the problem I have is finding out the height of the walls for example Wall A height is 2360mm and slopes to Wall B height being 1820 how do I find out if I have the correct wall heights?

Not sure if the following information is helpful or not.
Wall A is a High shed/gable wall
Wall B is a Knee Wall
Other two walls are Full gable walls


Many thanks for any help given.

Regards

/Hanna