Best way to animate a door close/open?

So I have a door model, and the problem is the PrimaryPart is a union, which I'm not sure if that works with tweening, do you have any suggestions for how I can animate this?

Every Instance can have it's properties tweened. All you have to do is specify that property in the Tween's TweenInfo.

By specifying properties in the TweenInfo, I mean it would look something like this:

local startTween = {
	Position = Vector3.new(0,0,0) -- Position is a PROPERTY of a base part.
}
local endTween= {
	Position = Vector3.new(0,10,0) -- Position is a PROPERTY of a base part.
}