I'm installing a click 'n lock floor. I put the recommended plastic foam underlayment/vapor barrier in and per instructions let it extend up about 2 inches around where the baseboards were removed and taped the underlayment that's sticking up with painters tape to the sheet rock walls before installing the floor.

I'm done now and am ready to reinstall the baseboards.

The question is: are you supposed to leave the underlayment sticking up and install the baseboards over the underlayment that's sticking up and then trim any of the remaining underlayment sticking out over the top of the baseboards ? Or are you supposed to trim off the underlayment that is sticking up all along where the floor meets the walls ?

Bob

The idea is to leave the vapor barrier up as much as possible behind the base, but you can only do that with a two part 6 mil poly barrier and underlayment. When using a 2in1 or 3in1 combination underlayment that has the moisture barrier already attached, I trim those off flush with the top of the flooring. The higher you can leave it the better off you will be in the long run.

Thanks alot Jerry. It's not very thick (though it IS the 2 in 1 combo with the foam and the vapor barrier). So I'll see if I can at least let it curl up a little behind the baseboard without creating any problems with caulking the top of the baseboards. The basebaords should compress it against the sheetrock pretty well.

Your explanation was consistent with my rookie instinct that it would be preferable to have the vapor barrier extend upwards a little if possible but if not, flush with the floor is okay.

Thanks again for taking the time,

Regards,

Bob

Yeah, the back of the base is recessed so if you can fold the corners tight you should be in good shape.