Yes, your carpentry level has to be level 11. Note that some recipes allow you to make things at a lower crafting level than the required using level, i.e. the Ventis et al sets from the windmill. Though these items aren't carpentry items, there are some carpentry items with this aspect too, can't remember which off-hand tho. With the Windmill sets, you can make them at 1st, 2nd, or 3rd level (crafting) and use at 15th, 20th, and 21st level (class) (an exception being the Ventis archmage boots which for some strange reason go: 15th, 20th, 16th). Only item I know of that loses level requirements with an upgrade in color.
Ciao,
Jhordan
