I am redoing the floor on the first floor of my house - concrete slab.
When I initially installed the floor about 10 years ago i used different underlayments in different rooms
If I install the new floor (using a thicker underlayment) almost butting it to existing baseboards, leaving about 1/4" gap on perimeter, covering that gap with quarterround.
Please see my previous post below, if the answer to my baseboard question is yes, i.e. I need to take them off. The answer to current question is moot.

 

Here is a link to the post: http://www.doityourself.com/forum/so...erlayment.html

Again, the question is if it is doable. To leave such a small gap between the laminate floor (that is probably does not expand and contract at the same rate as wood, but still) and the baseboard. I really don't want to deal with any buckling...
If that is not an option I may just use same thickness underlayment and use similar reducer to the one i used before.

 

It is not imperative that the baseboards be removed. Looks like you already have a bit of a gap under them anyway. Just make sure that the floor is centered so that any shifting will not expose the end of the cuts by peeking out from the shoe molding.

 

Thank you czizzi,

you see this is my concern, the space I have below the baseboard is not enough to bring the bedroom floor with the rest of the flooring in the hallway.
So if I want to keep the same level, i will have to almost butt it to the baseboard, i can not go under it. Will leaving 1/4" of gap all around enough for the temperature fluctuations.