[Tagging] [Indoor] is indoor=level walled ?

[PanierAvide]

Hello,

I'm currently working on a project involving editing of indoor features. 
Regarding Simple Indoor Tagging scheme :

"indoor=level is optional and not intended for rendering purposes, but 
for having a place to add additional information like a floor name"

So according to wiki, indoor=level doesn't involve having a implicit 
wall following the geometry. Is it something we agree on ?

In that case, if I need to create an explicit wall following the contour 
of the indoor=level feature, I should create another way with 
indoor=wall tag. According to wiki, indoor=wall can only be used on 
lines, so if I create a closed line, it should not render as an area 
(same behaviour as footways). Is it also something we agree on ?

Last question, if I want to create a wall as an area (imagine for 
example a wide pillar where no one can enter), should I just use 
indoor=wall + area=yes ?

Best regards,

-- 
Adrien P.