leveling a sill under a patio door

I have an 8 foot wide sliding door. the sill is aprox. 3/8 out of level over the length of it. How would you approach this job? A few shims and a lot of caulk?
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Replies
What is the sub-surface you are setting it on?
plywood on 2x joists
Lots of possibilities. Just a few..
1) Rip tapered shims off the edge of any 2x stock that is 8' long using a "skilsaw" (I like 2x6 , easier to control the saw on the wider stock ) Glue and pin or finish nail the shims down.
2) Set up an outside form that is level and snap a line that is level along an inside form , use "bondo" and fill the "form" to level. You can use floor patch for this but I prefer "bondo" type body fillers myself .
3)Commit heresy and set the door out of level and rack the frame to plumb, use the wheel adjusters to make the door adjustments for the out of level.
Thanks for all the ideas. I'm going to go with a solid tapered piece of wood and caulk.
That will work, pretty easy to do .Just make sure to glue it to the subfloor.
Band sawn long taperd wedge.
Spheramid Enterprises Architectural Woodworks
I have irriatable Vowel syndrome.
Are you saying the threshold sits on the floor, but because the floor is uneven it won't sit level without a gap between floor and threshold?
What's the finished floor going to be? If it hasn't been installed yet you should try to determine how the floor guy is going to deal with the out of level subfloor. Does the client know his floor is out of whack that much?
Beer was created so carpenters wouldn't rule the world.