You might want to add the file though Ryan!
I believe that you spent some time on that, and without seeing the file I'm going to make a few comments ... they may or may not be relevant:
- Truss manufacturers use differing butt cuts. The only way to know for sure the heel height is to get the actual butt cut from the truss supplier - I believe that Softplan uses a 1¾" butt cut. Our normal supplier uses a 1¼" butt cut.
- Truss heel height doesn't vary with wall thickness.
- If you are using rafters (as opposed to trusses), when you open the roof options in Softplan, If you input the pitch, rafter depth and input the seat cut as the wall width (or whatever you require), Softplan will automatically calculate the heel height.
- Depending on your location, you may need different heel heights on trusses. Under the Ontario Building Code, the minimum insulation over the top of the wall has to be R20. So no matter what the calculation comes out as, the trusses have to be manufactured with at least a 5½" heel height.
... and having done all that, Softplan will still calculate things wrongly, because it still INSISTS on putting the fascia up to the TOP of the roof sheathing.
Ryan ... apologies, reading this through again, it sound as If I'm being ungrateful. I would like to assure you that this is not the case, and I would like to see (and download) your Excel spreadsheet. I was just pointing out some issues.
I also have an Excel spreadsheet with butt cuts and heel heights etc. I'll post that on Saturday when I get back to work. There may be something on it that you can use too - (alternately, it gives you a chance to see where I screwed up ... ).