Adding more mass to basement ceiling

One of the main principles described by Gervais in his book, is that mass is the most critical factor to sound isolation. However, it is not just mass on the "room inside a room", but the mass on the other side of the wall that is equally important.

Ideally my main level floor would have contained multiple levels of plywood flooring, providing extra mass to the basement ceiling. This was not the case, however Gervais provides a solution. This consists of attaching multiple layers of drywall to the underside of the main level floor, between the joists.

As you would imagine, this is no easy task. My builders have begun the work, and it is certainly time consuming but worthwhile. My next post will contain photos of the work, and some slight differences to the diagram above, that will save a lot of time.

Cycas - free drafting software

Update (Jan 2012): I would now recommend Google Sketchup software.

After some research of Linux-compatible free drafting software, I eventually settled on Cycas (http://www.cycas.de/). There is some learning curve, but after a couple of hours, it became fairly easy to use. There is also a large amount of documentation and tutorials available with the program, even if the below par German-English translation makes it hard to understand (most learning came by just messing around with the software).

I plan to use Cycas to draw floorplans, and may try and use some of the more advanced features such as 3D povray rendering from any perspective inside the basement (the Cycas gallery is impressive).

Here is my first attempt at the basement floorplan (red represents wood studs, white walls are concrete).