A pocket door can only be installed if the wall is open. It requires different framing that makes the wall thicker. Don't do a barn door, they're on their way out and in a year, you'll regret the decision. I'd recommend the french door, but can you post some pictures of the space so we can get a better idea?

48" is too narrow unless you intend to always keep both sides open.

aside from the barn door going out of style, its not particularly effective at blocking noise.

oooo seeing your picture. i'd do a center hinged french door against a matching fixed panel, the door can open back against itself.

Don't go with thin sidelites, instead go with a 48" door opening with two 24" slabs and 12" sidelights. Anything less on the sidelites screams: "I really want sidelites but there really isn't enough room!"

One more note for NO barn doors. I have double barn doors in my master bedroom. Sure they look cool for now. However, they offer absolutely no privacy in regard to sound.

Thanks everyone!

@Carolina, ok, that is what I was thinking as well. Now I have to see if there are doors that come like this with the sidelights and transom or if I have to get a custom door.

@ninigret, I didn't think of your approach. That would actually allow me to get a bigger door without sidelights.

@sushipup1, I agree 24" is too thin, but my thought is the doors would either always stay open or be closed for the way I plan to use them.

@phuninthesun, that was my concern as well with regard to the noise.

it was easy for me... i have one just like it. : )

@ninigret, that looks nice - what is the width of the door?

@kidshop, I agree - I don't like the space that a swing door takes. That is why I thought with 24" double doors, the swing wouldn't be too much. I like your barn doors - they look great.

meluky, sorry i dont know the width... its at our vacation house and sadly, very sadly, i'm not there during the week.

I'm going to say none of above (if pocket doors not an option).... I see french doors in new construction offices all the time and all I can attribute it to is "what everyone is doing" because from a practicality issue it makes no sense to me. Most people's offices are for working in and are functional and private and often times, messy! Why would people want that to be "open" to everyone? You certainly don't want your guests to see it and it is even unappealing and even stressful to look at a space covered in piles and clutter. I know everyone's office is not this way but trust me :), most are not the tidiest rooms in the house! Put solid doors that offer noise control and privacy. Also gives you other options if for some reason it needs to serve another function at any time- i.e. guest room.