4 ways to finish your basement – wikihow
Finished basements can end up with mold and other moisture related problems behind the walls adjacent to the outer masonry walls. Be sure you or your contractor understand the details of waterproofing, minimal insulation, proper ventilation of wall cavities, and foregoing vapor barriers. Unless your stud-wall is at least 18″ away from the masonry wall, any vapor barrier attached to the stud wall will trap moisture between the masonry wall and the barrier, thus breeding mold.
Look for signs of water leakage before starting your project. Be sure to evaluate any water problems that could affect your finished basement to determine what repairs are needed and take preventative steps to avoid future water problems. Look outside for obvious potential problems like clogged rain gutters, downspouts emptying next to the foundation and surface grades that don’t allow surface water to run away from the property.
Make sure that you protect your investment by getting an emergency power supply and monitoring devices for your sump pump. If you rely on a sump pump to keep ground water out of your basement, consider a secondary pump as a backup in case your primary pump fails or, a battery backup secondary pump for power outages..
Ventilation and Dehumidification. Be aware that allowing outside “fresh air” into your basement via open windows or fans, can cause problems with moisture, humidity and condensation when outside humidity levels are above 40%. Get a good dehumidifier to mechanically remove the natural high humidity in your basement and keep your windows and doors closed all year round. Central air conditioning also offers good dehumidification.
Gather as much information as possible about it before you get started.
Be sure you understand that finishing a basement is a big project.