Finishing the basement of your house can pay rich dividends, not only will you have more usable space but you will also increase the value of your house by much more than what you will invest to get it done.
It is not always easy to get it done, but many resources are available to you on the net, and in your local Home Depot or similar shops. It is best if you do the work yourself as labor is the most expensive part of any refinishing project. However you will do a better job if you follow these guide lines.
First and foremost you must plan and draw your plans. Draw the room (or rooms) of your dreams, marking the walls, the wires, cables and all plumbing.
Make a list. Consult the net for Do it Yourself sites, or Home sites as this one to find out the materials you will use and the quantity you need for your project.
Inspect the area before starting work. Look at the foundation carefully to ensure that no cracks are present, verify that the basement is very dry. If any moisture exist consult my post on humid basement problems.
Plan cables and lighting layout. Get a building permit and your local regulations for electrical wiring. Ensure that the number of electric outlets is sufficient, and that phone lines and cables are well planned. It is better to have it and not need it, than to realize too late that you should have added an outlet in a specific location. If some part of the work is beyond you competence, and you need to hire a specialist make an appointment and have the basement inspected to confirm that all codes will be respected.
Time to get started with the walls building. Dry wall is ideal to cover concrete walls and create smooth surfaces that will be easy to paint, or to decorate even using inexpensive wall stickers. Once the frames are up consider using insulation before fastening the dry wall. Insulation will protect your basement further from energy loss and will provide a better acoustic environment for your music. Do not forget cables and plumbing access.
With the walls in place you can turn your attention to the floor. Basement floors are usually cold, since only a small layer of insulation protect them from a very cold ground. You should install a sub-floor before choosing the floor covering that you would like to use. Once the sub-floor in place you are free to choose any finishing, tiles, carpet or wood, your options are unlimited.
Finally with walls and floors finished it is time to finish the room with paint and baseboards, and to move in the TV and remote control.

