Rugs, Carpets and Carpeting - how do pro's butt carpet to h/w without transition piece?

I just put engineered h/w floor in a utility closet that is behind bifold doors which open onto a carpeted hallway.

I want to avoid transition piece for several reasons
1. I dont want to trim bottom of bifold doors
2. transition piece would show under closed doors and look bad
3. more work :)

I see many examples of a clean carpet line right up against tile, cedar floors in closets, etc.

1. how do they do this without having an ugly freying edge on carpet?

2. can I just fold carpet under itself and carefully tack down with tiny tacks?

3. do I need a carpet strip too or is the 'double layer' of carpet ok?

Thx!

Tackstrip, leaving a ¼" gap/gully for the carpet to tuck into. Stretch the carpet up on the tacks, sqirt latex seam sealer in the gully. Trim the carpet leaving it just long enough to tuck into the gully. Trim any loose nylon threads. Stay off of it long enough for the latex to set up.

thanks Perry
but when you say 'tuck' it into gulley that is formed between tackstrip and the finished edge of (in my case hardwood floor edge) do I FOLD the carpet back on itself?

I was thinking by folding it back under itself it creates a firmer edge that will not frey and will not DIP too low after it passes over tack strip... but I want to do what is standard.

in your suggestion, which way isthe unfinished edge of carpet oriented so you dont see it when looking straight down? if it is sitting in the bead of seam sealer, wouldnt you see all that when you look down at the edge?
THANKS!

If this is ¾" thick flooring you need to ramp the carpet to bring up the height.
www.carpetshims.com.

Or you can take a router to the edge of the board and make a rounded profile on the edge.