Determining attic floor space

[bchap56]

I'm planning out a new garage and am trying to determine how much attic space that I might have. I'm building a 20x40 one car with the last 18 feet being attic. The ceiling under the attic will be 8 feet. The other part will have scissor trusses to make the ceiling as high as possible for a future lift (hopefully). I don't want the roof peak to be higher than the house, so I can only go up 16 feet. Can anyone help me determine how much floor space I'll have in the attic with 5 feet or more of head room? I've attached my drawing if that helps.

 

[JSBriggs]

Do a quick elevation drawing. From there you can figure different floor/ceiling heights along with roof pitches and ceiling pitches to determine various clearances.

-Jeff

 

[bchap56]

ok, I think I figured it out. Drawing it really helped. It looks like I'll have 7 feet across of attic space 5 foot or higher.

 

[logical]

I think you may be cutting it a little close to only have 22 feet of high ceiling area & 18 of low ceiling with the future possibility of a lift. With the length of any ramps or even just considering leaving 3-4 feet behind the vehicle to work around it the front of a full size vehicle will be more than 22 feet in. I think a 24 & 16 split is even risky. I'd go 26 & 14. That attic area that's under 5' tall is still storage space.

Edit: I see you've kind of considered this in your drawing, but I still think you should get to at least 24.