Barry, Although Styrofoam is widely used as weather insulation it is not a very effective sound proffer. I can't quote you dB reduction figures for Styrofoam at this time but I can tell you that it is a poor sound absorber and sound barrier compared to other soundproofing materials. Fiberglass, especially rigid board fiberglass, sound matte products, and several other sound conditioning products (spray and paint on) will provide far better results than Styrofoam. In addition to my DeLorean knowledge I spent much of my carrier as a TV Studio Design and Operations Consultant. Application of sound proofing techniques, material application, and installation procedures were part of my contracted services. "We're here to help you" Seasons Greetings! DMC Help / De Lorean Services / <dmchelp@xxxx> Web Site: (TEMPORARY)<www.geocities.com/dmcjoe> ----- Original Message ----- From: <qrorell@xxxx> Subject: Re: [DML] Re: Road noise > If you look inside of the front door posts of most new cars you will see styrafoam is used for insulation. > It is the best and cheepest way to cut down noise. > Barry > 6012