Expert: John Michaels - 10/30/2009

Question
So my grandmother wants to install new carpet over the old existing carpet. I have tried to tell her it is not a good idea at all. I would like some general information of why it is a bad idea to do that, so that she won't. It is in a rental home and i want to help her do things the right way. She is very old fashioned and believes you can preserve anything if its been cleaned. Please help me to convince her to not install the new carpet over the old.

Answer
Hi Cassie;First, carpet was not designed to be padding, so installing carpet over carpet, which itself may be installed over padding, (if not glued, directly to the floor), makes the existing carpet padding.  That will cause the new carpet pile not able to properly recover from traffic, allowing the trafficked areas of the new carpet to become crushed and very visible.  It may also cause the new carpet not to hold a stretch, even if properly powerstretched.  Remember that any installer who installs carpet with just a knee kicker should be prohibited from installing any carpet for you.  A knee kicker is not a stretching tool.  It is used to position carpet.  A powerstretcher is the proper stretching tool, and it MUST be used in accordance with the diagram and instructions in The Carpet & Rug Institute's installation manuals, CRI-104 & CRI-105, 104 being for any commercial installation, and 105 being for any residential installation.

Also, if the new carpet becomes loose, continuous walking on loose carpet will cause a breakdown of the total construction of the new carpet, so it would have to be replaced.

Next, when new carpet is installed over existing carpet, you present the face of the existing carpet with a dark, warm, moist area for the growth of mildew, mold, and other living organisms.  Mildew and mold feed off those other living organisms.  You then create health issues which can be deadly to anyone living in the property.  I am NOT an attorney, but should such a horrible thing occur, the landlord (your grandmother), could be held responsible.

No matter how clean the existing carpet is, those microscopic living things are presented with a home, the face of the existing carpet.

Tell your Grandmother to believe me.  If she chooses not to believe me, then find out the name of the manufacturer of the new carpet she wishes to install, and visit the website of that manufacturer.  On that website will be contact information such as an 800#.  Call it and speak with their techical services department.  Ask them why existing carpet should not be a foundation for new carpet.  They may have some additional reasons, and may also tell your Grandmother that, should a claim arrise on the new carpet, the manufacturer would not stand behind any warranties that come with the new carpet.

Finally, I am a Grandfather, so have your Grandmother contact me and I will be glad to speak with her as a peer, and tell her NOT to install new carpet over existing carpet.

If you have any other questions, please feel free to contact me.

Cordially,

John Michaels