I've got a pretty simple 10 x 11 room I'm putting click-lock floor on a concrete base, with two walls forming a corner being external walls. Could somebody please explain how/where you snap a line or lines to guide you ? Is it at the starting wall and is the line the width of the board plus 1/2 inch expansion. Is there any reason for a line in the middle of the room or anywhere else ? Seemed to me since it clicks and locks there isn't a lot of latitude to move the floor around anyway.

I was planning on starting on the inner upper wall and working out towards the external wall and corner since the external wall end is in a closet so nobody can see if I have to rip a strip due to unparallel walls.

You do not need to snap a chalk line with click type floating floors. Just start putting them together according to the instructions that came with the flooring. It rarely matters which wall you start off of with a floater. If it's really wavy, you'll need to scribe your first course to the wall. Plan the install so the last course is at least 2" wide or wider, depending on the flooring. If it would be less, then you'll need to rip some of the first course to allow the last course to be wider. Use spacers at all walls. It really helps with the assembly and keeping things tight and true.

Now THAT makes sense ! THANKS so much Gary for clearing up the mystery, as I feel more confident now about tackling it this week.

Instructions say the GROOVE of the first course faces the starting wall. Doesn't make sense to me since you'd then be tapping on the tongues of the next courses which doesn't seem like a good idea. Seems it should be just the opposite.

And do you REALLY need 1/2 inch expansion for a small 10 x 10 room (which Bruce recommends) ? That only leaves 1/8 inch overlap by the 5/8 thick quarter round.

Thanks again for your help.

Bob

No, if you need to tap the boards together, you will need a tapping block made of plastic. Once placed against the sides of the tongues, you can hit it pretty hard without damage. Do it the way the instructions say with groove side to the wall. 1/2 expansion is perhaps overkill in your situation. 3/8" should be fine IF you maintain even temps and humidity.

I think I install those floors backwards, I put the tounge against the starting wall (with 1/2 in spacers) so the large groove part is in the room.
and I go right to left also, it clicks together much easier, and faster for me.
I have a tapping block, have yet to actually need it.