i want to replace old carpeting with laminate planking (underlayment attached) on concrete floor. laundry room is bare concrete with several layers of scratched paint. do i need to tape down a test plastic area in this room or one that has carpeting in it to see if there is a moisture problem. i live in a moist ground area.
It will never hurt to test for moisture but if you did have a moisture problem you should see some damage to the old carpet.
Since you are installing on a slab, make sure you upgrade the pad underneath the floating floor to a vapor barrier style that is rated for concrete use. This kind of pad will cost you about 50 cents per square foot as opposed to half the for a standard foam pad, but it is worth it.
i won't be installing until january, but have started getting info. it is a duplex i own and one side always has a musty smell when you go in. do you think that is a sign of moisture (i had them professionally cleaned two months ago). the carpeting doesn't feel damp but it is the old shag kind on that side. or do you think the odor is just because its old carpet. anyway, its coming out after the new year. thank you for your input.
Good chance that the musty odor is just the old carpet. Since you have a month to observe, then do so. When you pull up the old carpet, take a careful look at any discoloration on the back side - that will help indicate if there have been any serious moisture issues in the past.
jaybee: i have since discovered old laminate/vinyl tiles glued down to the concrete. i will be leaving them to floor over. do you think it is easier/best to lay a separate underlayment down or use planking with underlayment attached? also as room/floor temps are supposed to be 60+ i won't be installing for another couple months.
Was there a padding under the old shag. Some types of padding will develop a musky smell over time.
One such padding that was popular was referred to as " Horse Hair".
If you have any concerns about moisture I would go with a roll-out pad instead of the individual padded pieces. Either type pad makes the floating floor work but with the roll-out you can tape the seams so it also acts as a moisture barrier.