You CAN install laminate flooring over carpet, though generally not recommended.
More Info: Most installers and builders recommend NOT installing laminate flooring over carpet, as there are too many variables that can create a mess. You may be able to successfully install your laminate floor over carpeting as long as it is less than one-quarter inch thick, is set on suspended wood sub-floor, and is fully adhered.
Why not Just Tear Up the Carpet?
Homeowners may not want to go to all the trouble of tearing up carpet and padding. If you have severe allergies, stirring up all the dust and dirt that may be settled into the carpet could keep you sneezing for weeks. Additionally, disposing of the mass of carpeting could be a problem if you do not have access to a truck with which you can haul it away. Or if you live in a rental home, you may not be allowed to permanently modify the flooring.
When You Shouldn’t Put Laminate On Top of Carpet
Manufacturers generally do not recommend installing laminate flooring over top of carpeting. The reason for this is that the flooring needs a very stable surface upon which to rest. If there is a layer of fluffy, soft carpeting underneath it, your floor will have quite a bit of “bounce” to it as you walk upon it. Additionally, the weight of the furniture can cause the pieces of laminate to push away from one another leaving visible gaps in the floor. So if your carpet/pad combination is thicker than a quarter inch do not try this!
When You Can Put Laminate On Top of Carpet
According to the laminate flooring manufacturer Armstrong, you can install your laminate flooring over any area that has a flat sub-floor, is structurally sound, dry, and clean. In most circumstances it can be installed over wood, concrete, tile, vinyl sheet, and even carpeting as long as it is less than one-quarter inch thick, is set on suspended wood sub-floor, and is fully adhered. If your situation meets these criteria, then it is likely safe to install.
“Laminate FAQS from Armstrong.” Flooring, Ceiling and Cabinet Products by Armstrong. N.p., n.d. Web. 8 Nov. 2011. <http://www.armstrong.com/flooring/faqs-laminate.html>.
“Frequently Asked Flooring Questions – Great Western Flooring.” Chicago Floors by Great Western Flooring. N.p., n.d. Web. 9 Nov. 2011. <http://www.greatwesternflooring.com/faq